Update PostgreSQL/PostGIS images

Signed-off-by: Daniel Kastl <[email protected]>

Author: dkastl

.github/workflows/test-postgis.yml

@@ -27,7 +27,7 @@ jobs:
       matrix:
         redmine_version: [5.0-stable, 5.1-stable, master]
         ruby_version: ['3.0', '3.1', '3.2']
-        db_version: [12-3.0, 15-3.3]
+        db_version: [12-3.4, 16-3.4]
         include:
           - system_test: true
             redmine_version: 5.1-stable