qa-test-data: Ignore submodule git-status

With this change, untracked and committed new changes
in the submodule will not affect the check_mk repo git-status.

Change-Id: I9231952b5ff0a3e4e6b54b67ed25423b6c8dfe61

.gitmodules

@@ -2,3 +2,4 @@
 	path = tests/qa-test-data
         url = ../qa-test-data
 	branch = master
+	ignore = all