Add changelog.md to prettierignore

[siddharthkp]

I went into a silly rabbit hole of CI and come back with this:

• Noticed that CI is failing in Release tracking (37.3.0) #5234, because npm run format found unrelated changes in CHANGELOG.md
• This happens because changesets can no longer find our prettierConfig from package.json, it uses the default prettier config.
• This started happening last week with the upgrade to prettier from 3.0.0 to 3.3.3 chore(deps-dev): bump prettier from 3.0.3 to 3.3.3 #5180
• This was introduced in prettier 3.1.1 Implement our own config explorer prettier/prettier#15663. Related doc change: https://github.com/prettier/prettier/pull/15910/files
• Until changesets updates their prettier config code, adding CHANGELOG.md to .prettierignore
• changesets would still run prettier (default config) on CHANGELOG.md, but our format CI job will no longer complain about it

Rollout strategy

• Patch release
• Minor release
• Major release; if selected, include a written rollout or migration plan
• None; if selected, only affects CI

Testing & Reviewing

[github-actions]

size-limit report 📦

Path	Size
packages/react/dist/browser.esm.js	98.58 KB (0%)
packages/react/dist/browser.umd.js	98.94 KB (0%)