macos: Remove invalid 'exit /b'(?)
Trying to fix this:
cd "C:\Craft\BinaryFactory\" python craftmaster/Craftmaster.py --config craftmaster/config/CraftBinaryCache.ini --target windows-msvc2017_32-cl -c --target 5.2 kdevelop || exit /b --
... succeeds despite the logs indicating a failure:
08:29:30 Command C:\Program Files\Python36-32\python.exe -u C:\Craft\BinaryFactory\windows-msvc2017_32-cl\craft\bin\craft.py --target 5.2 kdevelop failed with exit code: 1