DOC-2383: Update Svelte Integration's Technical Reference page for TinyMCE V7 release.

[kemister85]

Ticket: DOC-2383

Site: Staging branch

Changes:

• Added licenseKey info
• Updated Svelte version table to match what is in tinymce-svelte README.md
• Updated event list to include the new events in v7.

Pre-checks:

• [x] Branch prefixed with feature/<version>/, hotfix/<version>/, staging/<version>/, or release/<version>/

Review:

• [x] Documentation Team Lead has reviewed