Update changelogs for v7.4.18, v7.5.9, and v7.6.4 - #27707

Update changelogs for v7.4.18, v7.5.9, and v7.6.4#27707

Justin Chung (jshigetomi) merged 2 commits into

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jshigetomi:changelog/v7.4.18-v7.5.9-v7.6.4jshigetomi/PowerShell:changelog/v7.4.18-v7.5.9-v7.6.4Copy head branch name to clipboard