Shell injection through main-dir

[AlexDaniel]

Ddt/lib/Ddt/Distribution.pm6

Lines 190 to 194 in c611e9c

	method !init-vcs-repo {
	my $git-dir = $.main-dir.absolute;
	shell("cd $git-dir && git init", :out).out.slurp-rest;
	shell("cd $git-dir && git add .", :out).out.slurp-rest;
	}

↑ I don't know how dangerous that is, but I'd much rather not see shell being used there…