fix(spanner): only set snapshot isolation read timestamp for SI or optimistic txns in CloudClientExecutor - #14346

🤖 I have created a release *beep* *boop*
---


<details><summary>1.92.0</summary>

##
[1.92.0](v1.91.0...v1.92.0)
(2026-09-23)


### Features

* **bigquery-jdbc:** add `EnableTimestampPicos` connection property and
its plumbing
([#14284](#14284))
([b4aa5ac](b4aa5ac))
* **bigquery-jdbc:** implement picosecond temporal math and formatting
engine
([#14286](#14286))
([2a9612a](2a9612a))
* **bigquery-jdbc:** support picosecond in REST JSON path and nested
types
([#14334](#14334))
([15ffe4a](15ffe4a))
* **bigquery-jdbc:** support picosecond in `PreparedStatement`
parameters and batching
([#14373](#14373))
([c1aac66](c1aac66))
* **bigquery-jdbc:** support picosecond timestamp in `ResultSetMetaData`
and `DatabaseMetaData`
([#14358](#14358))
([43acdd3](43acdd3))
* **bigquery-jdbc:** support picosecond timestamps in Arrow Storage Read
API and nested types
([#14332](#14332))
([b5d9aca](b5d9aca))
* **bigquery-jdbc:** support qualified project delimiter in
`DefaultDataset` property
([#14240](#14240))
([6e8d6c8](6e8d6c8))
* **bigquery:** accelerate row-based query() with Arrow wire format
([#14405](#14405))
([8d12a8f](8d12a8f))
* **bigquery:** add ArrowDeserializer helper utility
([#13943](#13943))
([d9a298b](d9a298b))
* **bigquery:** add ArrowQueryPageFetcher for Arrow query result
pagination
([#14404](#14404))
([615409f](615409f))
* **bigquery:** add ArrowQueryResult and ArrowQueryResultImpl for Arrow
result streaming
([#13944](#13944))
([a62fdf8](a62fdf8))
* **bigquery:** add Storage Read API slow-path fallback for row-based
query()
([#14409](#14409))
([26e568a](26e568a))
* **bigquery:** add zero-copy queryArrow API for Arrow VectorSchemaRoot
streaming
([#14402](#14402))
([b44ffe8](b44ffe8))
* **bigquery:** make BigQuery AutoCloseable with default no-op close
method
([#14434](#14434))
([00bf3de](00bf3de))
* **firestore:** add support for BSON types
([#13189](#13189))
([8a123d9](8a123d9))
* **gax:** add ApiCallContext and request-level settings overloads to
ResumableUploadCallable
([#14251](#14251))
([e8cbd42](e8cbd42))
* **gax:** add globalTimeout settings field to
ResumableUploadCallSettings
([#14253](#14253))
([438cda6](438cda6))
* **gax:** add resumable upload error classification and retry algorithm
([#14419](#14419))
([b70396d](b70396d))
* **gax:** add ResumableUploadCallable creation to Callables and
HttpJsonCallableFactory
([#14242](#14242))
([7de24de](7de24de))
* **gax:** implement baseline Callable and Future for resumable uploads
([#14241](#14241))
([5a54db9](5a54db9))
* **generator:** add model flag and allowlist parser for resumable
upload RPCs
([#14317](#14317))
([acc1856](acc1856))
* **generator:** emit resumable upload client surface
([#14319](#14319))
([a9fed00](a9fed00))
* **generator:** emit resumable upload settings and HttpJson upload stub
([#14321](#14321))
([c122474](c122474))
* **generator:** enable resumable upload generation for showcase
([#14325](#14325))
([f9ebd79](f9ebd79))
* **generator:** switch resumable upload specialized stubs to package
private
([#14471](#14471))
([0d4e875](0d4e875))
* **generator:** wire transport stub delegation to resumable upload
stubs
([#14322](#14322))
([cc4b980](cc4b980))
* **google/cloud/backupdr/v1beta:** add backupdr
([#14410](#14410))
([a4a47da](a4a47da))
* **google/cloud/networkservices/v1beta1:** add networkservices
([#14407](#14407))
([21c4955](21c4955))
* **pubsub:** add publish telemetry headers for publish attempt
observability
([#14338](#14338))
([c167ab8](c167ab8))
* **pubsub:** implement publish hedging to reduce tail latency
([#13735](#13735))
([b302615](b302615))
* **spanner:** Support dynamic TLS certificate and key rotation for
Spanner Omni
([#14456](#14456))
([ffc745c](ffc745c))
* **storage/control:** add delete folder recursive sample
([#13642](#13642))
([f4b1b46](f4b1b46))
* **storage/control:** add delete folder recursive sample
([#14397](#14397))
([2c01d55](2c01d55))


### Bug Fixes

* **auth:** restore transportFactory upon deserialization in
InternalAwsSecurityCredentialsSupplier
([#14340](#14340))
([beea42f](beea42f))
* **bigquery-jdbc:** ensure row ordering in PCNT IT
([#14330](#14330))
([a16f048](a16f048))
* **bigquery-jdbc:** fix htapi fallback due to permission logic
([#14418](#14418))
([21e6dc8](21e6dc8))
* **bigquery-jdbc:** fix Timestamp assertions
([#14290](#14290))
([533ba14](533ba14))
* **bigquery-jdbc:** handle null parameters in Storage Write API bulk
inserts
([#14270](#14270))
([dd2c41a](dd2c41a)),
refs
[#14066](#14066)
* **bigquery-jdbc:** handle SQL NULLs in ResultSet primitive getters
([#14383](#14383))
([8e464fe](8e464fe)),
refs
[#14371](#14371)
* **bigquery:** default Arrow pagination stream location to US instead
of global
([#14458](#14458))
([2775eb1](2775eb1))
* **bigquery:** preserve page token and paginate correctly in Arrow
query when maxResults is set
([#14469](#14469))
([f5601f4](f5601f4))
* **bigquery:** use first page row count for Arrow query pagination
offset
([#14466](#14466))
([9d10dd0](9d10dd0))
* **bigtable:** don't notify config listeners while holding the manager
lock
([#14294](#14294))
([4426ccd](4426ccd))
* **bigtable:** fall back to classic path when per-RPC CallCredentials
are set on session path
([#14477](#14477))
([57bacb0](57bacb0))
* **bigtable:** fix abnormal session closures and scale-up in session
pool
([#14431](#14431))
([6361ecd](6361ecd))
* **biqguery:** fix undeclared QueryParameter wiring in QueryStatistics
([#14401](#14401))
([64cf1d3](64cf1d3))
* **bom:** restore google-cloud-spanner-jdbc to libraries-bom
([#14362](#14362))
([bc7be5e](bc7be5e)),
refs
[#14347](#14347)
* **spanner:** honor maxAttempts and totalTimeout in streaming resume
loop
([#14370](#14370))
([305f47d](305f47d))
* **spanner:** only set snapshot isolation read timestamp for SI or
optimistic txns in CloudClientExecutor
([#14346](#14346))
([54c0d0f](54c0d0f))
* **spanner:** prevent statement cancellation race in
AbstractBaseUnitOfWork
([#14283](#14283))
([d9a8eef](d9a8eef))
* **spanner:** re-enable ITInstanceAdminTest on cloud-devel and
cloud-staging
([#14281](#14281))
([89a8268](89a8268))


### Performance Improvements

* **spanner:** stop re-parsing the request id on every RPC
([#14353](#14353))
([46108f4](46108f4))


### Documentation

* Add a Http/Json Post-Quantum Cryptography Guide
([#13963](#13963))
([fcc65b0](fcc65b0))
* **bigquery:** add QueryArrow code sample and document JDK 17+ JVM
requirements
([#14437](#14437))
([bd363f6](bd363f6))
</details>

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Co-authored-by: release-please[bot] <55107282+release-please[bot]@users.noreply.github.com>