test: fix risky test - add assertion count to testGCRejectsNonInt

Author: gr8man

tests/system/Session/Handlers/Database/AbstractHandlerTestCase.php

@@ -134,7 +134,7 @@ public function testGCRejectsNonInt(): void
                 $handler->gc($malicious); // @phpstan-ignore argument.type
                 $this->fail('TypeError expected for value: ' . gettype($malicious));
             } catch (TypeError) {
-                // Expected — type hint blocks SQL injection
+                $this->addToAssertionCount(1);
             }
         }
     }