cleanup [test]: add .runAsStressTest() to a Benchmark

GitOrigin-RevId: b825cdcabfaa5d958225b469abc8a26d67e637f1

platform/platform-tests/testSrc/com/intellij/openapi/vfs/encoding/FileEncodingTest.java

@@ -1090,7 +1090,7 @@ public class FileEncodingTest implements TestDialog {
       }
       encodingManager.waitAllTasksExecuted();
       UIUtil.dispatchAllInvocationEvents();
-    }).start();
+    }).runAsStressTest().start();
   }
 
   @Test