[BUGFIX] Can't remove static templates from selection in template module

Add missing '$' in front of formEl

Resolves: #56221
Releases: 6.2
Change-Id: Ia9b3260eebd007a60a34c33ac357fa84c572c8ac
Reviewed-on: https://review.typo3.org/27820
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters
Reviewed-by: Jost Baron
Tested-by: Jost Baron