[TASK] Cleanup sysext "taskcenter" and "tsconfig_help"

Change-Id: I2658e5d0a7ae979f93b60713294adcbe8e41db09
Resolves: #46145
Releases: 6.1
Reviewed-on: https://review.typo3.org/18822
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn