[TASK] Migrate EXT:backend Tabs.js to TypeScript

Resolves: #82604
Releases: master
Change-Id: I9b9ff38c635902f2713602955ad9a3d04734ec88
Reviewed-on: https://review.typo3.org/54367


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Andreas Fernandez <typo3@scripting-base.de>
Tested-by: Andreas Fernandez <typo3@scripting-base.de>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>