Remove core/extras dirs from old PRs during CI.

test/utils/shippable/shippable.sh

@@ -24,6 +24,9 @@ pip list --disable-pip-version-check
 export PATH="test/runner:${PATH}"
 reorganize-tests.sh # temporary solution until repositories are merged
 
+# remove empty core/extras module directories from PRs created prior to the repo-merge
+find lib/ansible/modules -type d -empty -print -delete
+
 function cleanup
 {
     if [ "$(ls test/results/coverage/)" ]; then