build: update releaserc to ensure we have a "release" branch

[brian-smith-tcril]

Semantic release requires at least 1 branch be configured as "release" (see https://github.com/semantic-release/semantic-release/blob/master/docs/usage/workflow-configuration.md#branches-properties)

Before this change we had 2 "maintenance" branches and 1 "pre-release" branch, but no "release" branch. This led to an error https://github.com/openedx/paragon/actions/runs/12286316911/job/34286199225

Description

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✅ Deploy Preview for paragon-openedx-v22 ready!

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.42%. Comparing base (3a62f9e) to head (3c44601).
Report is 4 commits behind head on release-22.x.

Additional details and impacted files

@@              Coverage Diff              @@
##           release-22.x    #3345   +/-   ##
=============================================
  Coverage         93.42%   93.42%           
=============================================
  Files               250      250           
  Lines              4515     4515           
  Branches           1017     1051   +34     
=============================================
  Hits               4218     4218           
+ Misses              294      291    -3     
- Partials              3        6    +3     

☔ View full report in Codecov by Sentry.
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[openedx-semantic-release-bot]

🎉 This PR is included in version 23.0.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀

[openedx-semantic-release-bot]

🎉 This PR is included in version 22.12.0 🎉

The release is available on:

• npm package (@release-22.x dist-tag)
• GitHub release

Your semantic-release bot 📦🚀