Fix 4537 by removing exports from package.json files

[heath-freenome]

Reasons for making this change

Fixes #4537 by removing exports block from the package.json files for each packages directory

• Updated all package.json files to remove the exports block from them
• Updated the CHANGELOG.md file accordingly

Checklist

• I'm updating documentation
  • I've checked the rendering of the Markdown text I've added
• I'm adding or updating code
  • I've added and/or updated tests. I've run npx nx run-many --target=build --exclude=@rjsf/docs && npm run test:update to update snapshots, if needed.
  • I've updated docs if needed
  • I've updated the changelog with a description of the PR
• I'm adding a new feature
  • I've updated the playground with an example use of the feature