Add root password

Author: schlessera

features/config-create.feature

@@ -204,7 +204,7 @@ Feature: Create a wp-config file
     Then STDERR should be empty
 
     # We try to account for the warnings we get for passing the password on the command line.
-    When I try `MYSQL_HOST=localhost WP_CLI_TEST_DBHOST='localhost:{SOCKET}' {RUN_DIR}/install-package-tests`
+    When I try `MYSQL_HOST=localhost WP_CLI_TEST_DBHOST='localhost:{SOCKET}' WP_CLI_TEST_DBROOTPASS='root' {RUN_DIR}/install-package-tests`
     Then STDOUT should contain:
       """
       Detected MySQL