Add 7.4.7 Changelog

[jshigetomi]

PR Summary

This pull request includes updates to the CHANGELOG/7.4.md file to document the changes and improvements made in version 7.4.7. The most important changes include build and packaging improvements, as well as updates to documentation and help content.

Build and Packaging Improvements:

• Updated branch for release and fixed backport mistakes.
• Fixed seed max value for Container Linux CI and added a way to use only NuGet feed sources.
• Bumped Microsoft.PowerShell.PSResourceGet to version 1.0.6.
• Various internal updates including pool changes, firewall monitoring, and typo fixes.
• Fixed release pipeline errors and switched to KS3.

Documentation and Help Content:

• Updated notices file.

PR Context

PR Checklist

• PR has a meaningful title
  • Use the present tense and imperative mood when describing your changes
• Summarized changes
• Make sure all .h, .cpp, .cs, .ps1 and .psm1 files have the correct copyright header
• This PR is ready to merge and is not Work in Progress.
  • If the PR is work in progress, please add the prefix WIP: or [ WIP ] to the beginning of the title (the WIP bot will keep its status check at Pending while the prefix is present) and remove the prefix when the PR is ready.
• Breaking changes
  • None
  • OR
  • Experimental feature(s) needed
    • Experimental feature name(s):
• User-facing changes
  • Not Applicable
  • OR
  • Documentation needed
    - [ ] Issue filed:
• Testing - New and feature
  • N/A or can only be tested interactively
  • OR
  • Make sure you've added a new test if existing tests do not effectively test the code changed
• Tooling
  • I have considered the user experience from a tooling perspective and don't believe tooling will be impacted.
  • OR
  • I have considered the user experience from a tooling perspective and opened an issue in the relevant tool repository. This may include:
    • Impact on PowerShell Editor Services which is used in the PowerShell extension for VSCode
      (which runs in a different PS Host).
      • Issue filed:
    • Impact on Completions (both in the console and in editors) - one of PowerShell's most powerful features.
      • Issue filed:
    • Impact on PSScriptAnalyzer (which provides linting & formatting in the editor extensions).
      • Issue filed:
    • Impact on EditorSyntax (which provides syntax highlighting with in VSCode, GitHub, and many other editors).
      • Issue filed:

[jshigetomi]

/azp run PowerShell-CI-macos, PowerShell-CI-Linux, PowerShell-CI-Windows, PowerShell-Windows-Packaging, PowerShell-CI-static-analysis, PSResourceGet ACR

[azure-pipelines]

Azure Pipelines successfully started running 3 pipeline(s).

[jshigetomi]

/azp run PowerShell-CI-macos, PowerShell-CI-Linux, PowerShell-CI-Windows, PowerShell-Windows-Packaging-CI, PowerShell-CI-static-analysis, PSResourceGet ACR

[azure-pipelines]

Azure Pipelines successfully started running 3 pipeline(s).