Merge pull request #160 from nextcloud/fix/makefile

fix(makefile): Don't add stubs directory to release

Author: marcelklehr

makefile

@@ -103,6 +103,7 @@ appstore: clean
 	--exclude=phpunit*xml \
 	--exclude=tests \
 	--exclude=ci \
+	--exclude=stubs \
 	--exclude=vendor/bin \
 	$(project_dir) $(sign_dir)/$(app_name)
 	@if [ -f $(cert_dir)/$(app_name).key ]; then \