Add release branches

[BernieWhite]

Related to microsoft/PSRule#1431

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Currently the PSRule action support specific releases:

- name: Run PSRule analysis
  uses: microsoft/ps-rule@v2.7.0

Or latest commit:

- name: Run PSRule analysis
  uses: microsoft/ps-rule@main

However we should provide some additional options to provide even more flexibility such as:

• microsoft/ps-rule@v2 - The latest stable release >= 2.0.0 and < 3.0.0
• microsoft/ps-rule@latest - The latest stable release.

When PSRule v3 is available microsoft/ps-rule@v3.