Document that target can be a branch

[TravisEz13]

Based on https://github.com/microsoft/coe-starter-kit/blob/3d5598bcef607055d41bcaf9c11538558254e3a3/CenterofExcellenceResources/Release/Pipelines/CoEStarterKit/create-github-release.yml#L201 , this input can be a branch name. Please confirm. Hopefully, I'll be able to confirm soon.

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[prmerger-automator[bot]]

@TravisEz13 : Thanks for your contribution! The author(s) have been notified to review your proposed change.

[prmerger-automator[bot]]

@TravisEz13 : Thanks for your contribution! The author(s) have been notified to review your proposed change.

[learn-build-service-prod[bot]]

Learn Build status updates of commit 8ca0542:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
task-reference/github-release-v1.md	:white_check_mark:Succeeded

For more details, please refer to the build report.

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[steved0x]

@TravisEz13 Sorry for the long delay, and thank you for making this PR. This task just calls the GH API for creating a release, and that parameter is described as target_commitish: Specifies the commitish value that determines where the Git tag is created from. Can be any branch or commit SHA. Unused if the Git tag already exists. Default: the repository's default branch.

https://docs.github.com/en/rest/releases/releases?apiVersion=2022-11-28#create-a-release

The GitHub action version of the task says the same thing. I am merging this PR and thank you for making the PR and helping to improve the docs.