PS7 should revert to defaults if it can't load user powershell.config.json #27370

PS7 starts, perhaps a warning message that it's using defaults (including `$profile`)

PS7 fails to start

Unhandled exception. System.Management.Automation.PSInvalidOperationException: PowerShell has stopped working because of a security issue: Cannot read the configuration file: C:\Users\bburns\OneDrive - Microsoft\Documents\PowerShell\powershell.config.json
---> System.IO.IOException: The cloud file provider is not running. : 'C:\Users\bburns\OneDrive - Microsoft\Documents\PowerShell\powershell.config.json'.
   at System.IO.RandomAccess.ReadAtOffset(SafeFileHandle handle, Span`1 buffer, Int64 fileOffset)
   at System.IO.Strategies.OSFileStreamStrategy.Read(Span`1 buffer)
   at System.IO.Strategies.BufferedFileStreamStrategy.ReadSpan(Span`1 destination, ArraySegment`1 arraySegment)
   at System.IO.StreamReader.ReadBuffer(Span`1 userBuffer, Boolean& readToUserBuffer)
   at System.IO.StreamReader.ReadSpan(Span`1 buffer)
   at Newtonsoft.Json.JsonTextReader.ReadData(Boolean append, Int32 charsRequired)
   at Newtonsoft.Json.JsonTextReader.ParseValue()
   at Newtonsoft.Json.JsonReader.ReadForType(JsonContract contract, Boolean hasConverter)
   at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Deserialize(JsonReader reader, Type objectType, Boolean checkAdditionalContent)
   at Newtonsoft.Json.JsonSerializer.DeserializeInternal(JsonReader reader, Type objectType)
   at Newtonsoft.Json.JsonSerializer.Deserialize[T](JsonReader reader)
   at System.Management.Automation.Configuration.PowerShellConfig.ReadValueFromFile[T](ConfigScope scope, String key, T defaultValue)
   --- End of inner exception stack trace ---
   at System.Management.Automation.Configuration.PowerShellConfig.ReadValueFromFile[T](ConfigScope scope, String key, T defaultValue)
   at System.Collections.Concurrent.ConcurrentDictionary`2.GetOrAdd(TKey key, Func`2 valueFactory)
   at System.Management.Automation.Utils.GetPolicySettingFromConfigFile[T](ConfigScope[] preferenceOrder)
   at System.Management.Automation.Utils.GetPolicySetting[T](ConfigScope[] preferenceOrder)
   at Microsoft.PowerShell.CommandLineParameterParser.GetConfigurationNameFromGroupPolicy()
   at Microsoft.PowerShell.ConsoleHost.ParseCommandLine(String[] args)
   at Microsoft.PowerShell.UnmanagedPSEntry.Start(String[] args, Int32 argc)
   at Microsoft.PowerShell.ManagedPSEntry.Main(String[] args)

[process exited with code 3762504530 (0xe0434352)]
You can now close this terminal with Ctrl+D, or press Enter to restart.