[BUGFIX] Add trim to modificators in TS-Parser

It is documented that modificators are trimmed in
TypoScriptParser. But since #54856 they aren't trimmed anymore.
That's why f.e. "addToList (value)" will not be executed.

Resolves: #62188
Related: #54856
Releases: master,6.2
Change-Id: I3828b22a836656ec808ac5d770d58803b9195102
Reviewed-on: http://review.typo3.org/33303
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>