Update the releasing documentation

[xylar]

This pull request updates the release process documentation in docs/developers_guide/releasing.rst to clarify version bump procedures, dependency updates, and conda-forge feedstock management. The changes aim to streamline the release workflow and ensure consistency across steps.

Updates to Version Bump and Dependency Management:

• Clarified that version numbers must be manually updated in mpas_analysis/version.py and ci/recipe/meta.yaml, with examples for release candidates (e.g., 1.3.0rc1).
• Simplified dependency update instructions, emphasizing the use of the GitHub "Compare" feature to identify changes between releases.

Enhancements to Release Tagging:

• Added detailed steps for tagging releases on GitHub, including generating release notes and marking pre-releases when applicable.

Improvements to Feedstock Update Process:

• Introduced a preferred method for automatic feedstock updates via the regro-cf-autotick-bot, with fallback instructions for manual updates if the bot PR is delayed or unavailable.

Post-Release Verification:

• Added a new section on verifying the release by installing the package in a clean environment and optionally announcing the release on communication channels. (docs/developers_guide/releasing.rstL15-R107)

Checklist

• Developer's Guide has been updated
• Documentation has been built locally and changes look as expected