docs: update CONTRIBUTING guide with changesets

[brionmario]

Purpose

This pull request adds comprehensive documentation for the project's release and versioning process, including clear instructions for both contributors and maintainers on using Changesets and the automated release workflow.

Release and Versioning Documentation:

• Added a new "Releases" section to CONTRIBUTING.md detailing how to manage versioning and releases using Changesets, including when and how to create a changeset for your pull request.
• Provided a step-by-step guide for contributors on creating changesets, including what types of changes require a changeset and how to write effective summaries.

Maintainer Release Automation:

• Documented the automated release process for maintainers, including how GitHub Actions and NPM publishing are triggered, and emphasized the importance of using automated workflows over manual releases.
• Listed available scripts for maintainers to manage versions, publish packages, and aggregate changelogs, with instructions on their usage.

Related Issues

• N/A

Related PRs

• N/A

Checklist

• Followed the CONTRIBUTING guidelines.
• Manual test round performed and verified.
• Documentation provided. (Add links if there are any)
• Unit tests provided. (Add links if there are any)

Security checks

• Followed secure coding standards in http://wso2.com/technical-reports/wso2-secure-engineering-guidelines?
• Confirmed that this PR doesn't commit any keys, passwords, tokens, usernames, or other secrets?

[asgardeo-github-bot]

⚠️ No Changeset found

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go.

If these changes should result in a version bump, you need to add a changeset.

Refer Release Documentation to learn how to add a changeset.

[brionmario]

⚠️ No Changeset found

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go.
If these changes should result in a version bump, you need to add a changeset.

Refer Release Documentation to learn how to add a changeset.

This is a document update.
No changeset is needed.