Fix github tests

Author: alexandermeindl

.github/workflows/tests.yml

@@ -10,12 +10,9 @@ jobs:
 
     strategy:
       matrix:
-        ruby: ['3.0', '3.1', '3.2']
-        redmine: ['5.0-stable', '5.1-stable', 'master']
+        ruby: ['3.1', '3.2', '3.3']
+        redmine: ['6.0-stable', 'master']
         db: ['postgres', 'mysql']
-        exclude:
-          - ruby: '3.2'
-            redmine: 5.0-stable
       fail-fast: false
 
     services: