Added checks for group deletion to UserGroupDatabaseTest

Request: MO
Change-Id: Ic63d7481472ef57e0816c499984f08715887c26c

Author: TheTechnolog

minion/src/test/java/io/bdeploy/minion/user/UserGroupDatabaseTest.java

@@ -66,6 +66,10 @@ void testGroupScopedPermission(MinionRoot root) {
 
         // ensure that removing the user from a group that they are not in doesn't break
         users.removeUserFromGroup(g.id, userName);
+
+        // test user group deletion
+        groups.deleteUserGroup(g.id);
+        assertNull(groups.getUserGroup(g.id));
     }
 
     @Test
@@ -103,6 +107,10 @@ void testGroupGlobalPermission(MinionRoot root) {
 
         // ensure that removing the user from a group that they are not in doesn't break
         users.removeUserFromGroup(g.id, userName);
+
+        // test user group deletion
+        groups.deleteUserGroup(g.id);
+        assertNull(groups.getUserGroup(g.id));
     }
 
     @Test