chore(deps): bump tinymce from 5.10.7 to 5.10.8 in /definitions

Bumps [tinymce](https://github.com/tinymce/tinymce/tree/HEAD/modules/tinymce) from 5.10.7 to 5.10.8.
- [Changelog](https://github.com/tinymce/tinymce/blob/5.10.8/modules/tinymce/CHANGELOG.md)
- [Commits](https://github.com/tinymce/tinymce/commits/5.10.8/modules/tinymce)

---
updated-dependencies:
- dependency-name: tinymce
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <[email protected]>