DOC-2466: TinyMCE 7.2.1 Release notes & community changelog

[FarzadHayat]

Ticket: DOC-2466

Site: Release notes Site: Changelog

Changes:

• Branch contains all individual release-note entries for TinyMCE 7.2.1 release documentation.

Pre-checks:

• [x] Branch prefixed with feature/<version>/, hotfix/<version>/, staging/<version>/, or release/<version>/
• [x] modules/ROOT/nav.adoc has been updated (if applicable)
• [x] Files has been included where required (if applicable)
• [x] Files removed have been deleted, not just excluded from the build (if applicable)
• [x] Files added for New product features, and included a release note entry.

Review:

• [x] Documentation Team Lead has reviewed