Crash if no branch is checked out when koha-qa.pl is run

Here is one example commit where it crashes. Happened on a fresh koha-testing-docker.

It doesn't come back to the right commit in the end.

git checkout 36d46c6510

kohadev-koha@kohadevbox:/kohadevbox/koha$ /kohadevbox/qa-test-tools/koha-qa.pl -v 2 -c 1
testing 1 commit(s) (applied to ea725f4 '24 Bug 25761: (QA follow-up) Consiste')

Processing files before patches
sh: 1: Syntax error: "(" unexpected100.00%)        #1st BAD STUFF HERE##############

Processing files after patches
|========================>| 4 / 4 (100.00%)

 OK	Koha/EDI.pm
   OK	  critic
   OK	  forbidden patterns
   OK	  git manipulation
   OK	  pod
   OK	  pod coverage
   OK	  spelling
   OK	  valid

 OK	Koha/Edifact/Line.pm
   OK	  critic
   OK	  forbidden patterns
   OK	  git manipulation
   OK	  pod
   OK	  pod coverage
   OK	  spelling
   OK	  valid

 OK	t/EdiInvoice.t
   OK	  critic
   OK	  forbidden patterns
   OK	  git manipulation
   OK	  pod
   OK	  spelling
   OK	  valid

 OK	t/Edifact.t
   OK	  critic
   OK	  forbidden patterns
   OK	  git manipulation
   OK	  pod
   OK	  spelling
   OK	  valid


Processing additional checks OK!
sh: 1: Syntax error: "(" unexpected
kohadev-koha@kohadevbox:/kohadevbox/koha$ %                                                                                                                                                           /h/d/d/k/koha-testing-docker ❯❯❯                                                                                                                                                               ✘ 137