[BUGFIX] Buttongroup for icons in toolbar not floated to the left

Fix a left over for removing styles which were missed in #61890

Resolves: #62064
Releases: master
Change-Id: I8121e901986cfa40388eba53f073184dc9b7f317
Reviewed-on: http://review.typo3.org/33176
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Georg Ringer <georg.ringer@gmail.com>