Improve CI workflow to await database

Author: SimonFrings

tests/wait-for-mysql.sh

@@ -3,6 +3,6 @@
 CONTAINER="mysql"
 USERNAME="test"
 PASSWORD="test"
-while ! docker exec $CONTAINER mysql --user=$USERNAME --password=$PASSWORD -e "SELECT 1" >/dev/null 2>&1; do
+while ! docker exec $CONTAINER mysql --host=127.0.0.1 --port=3306 --user=$USERNAME --password=$PASSWORD -e "SELECT 1" >/dev/null 2>&1; do
     sleep 1
 done