Update mysql Docker tag to v5.7.44

Author: renovate[bot]

Diff for: .github/workflows/main.yml

@@ -19,7 +19,7 @@ jobs:
 
     services:
       mysql:
-        image: mysql:5.7.10
+        image: mysql:5.7.44
         ports:
           # Another version of MySQL is installed on the vm and already uses the port 3306.
           - 3308:3306