chore(textfield,textarea): add migration guide to changelog

[marissahuysentruyt]

Description

How and where has this been tested?

Please tag yourself on the tests you've marked complete to confirm the tests have been run by someone other than the author.

Validation steps

Regression testing

Validate:

1. The documentation pages for at least two other components are still loading, including:

• [ ] The pages render correctly, are accessible, and are responsive.

2. If components have been modified, VRTs have been run on this branch:

• [ ] VRTs have been run and looked at.
• [ ] Any VRT changes have been accepted (by reviewer and/or PR author), or there are no changes.

Screenshots

To-do list

• [ ] I have read the contribution guidelines.
• [ ] I have updated relevant storybook stories and templates.
• [ ] I have tested these changes in Windows High Contrast mode.
• [ ] If my change impacts other components, I have tested to make sure they don't break.
• [ ] If my change impacts documentation, I have updated the documentation accordingly.
• [ ] ✨ This pull request is ready to merge. ✨

[changeset-bot[bot]]

⚠️ No Changeset found

Latest commit: 18bbf04d4de9b932f255ddc554ad09ca4de8ea12

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.

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[github-actions[bot]]

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Total size: 4.26 MB^*

🎉 No changes detected in any packages

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