Fix crash when starting with empty controller name

Status Job ID Name Coverage
  Build
passed #1035
docker
build-publish

00:00:25

passed #1034
docker
build-test

00:00:58

 
  Test
failed #1036
docker allowed to fail
static-analysis

00:00:20

passed #1037
docker
test

00:00:20

71.0%
 
  Package
passed #1038
docker
package-AppImage

00:00:25

 
Name Stage Failure
failed
static-analysis Test
      46     12    427      2      74 Looper::process@110-183@src/looper.cxx
62 21 400 2 93 GridLogic::pressed@129-221@src/gridlogic.cxx
69 14 523 2 97 gui_header_callback@97-193@src/gui.cxx
328 79 2878 1 342 Gui::keyboardHandler@565-906@src/gui.cxx
==========================================================================================
Total nloc Avg.NLOC AvgCCN Avg.token Fun Cnt Warning cnt Fun Rt nloc Rt
------------------------------------------------------------------------------------------
19532 14.6 3.0 103.7 604 32 0.05 0.36
ERROR: Job failed: exit code 1