Merge branch 'dl/test-must-fail-fixes-5'

The effort to avoid using test_must_fail on non-git command continues. * dl/test-must-fail-fixes-5: lib-submodule-update: pass 'test_must_fail' as an argument lib-submodule-update: prepend "git" to $command lib-submodule-update: consolidate --recurse-submodules lib-submodule-update: add space after function name