do not flag dead code if custom JUnit runner is used (IDEA-25444)

java/java-tests/testData/inspection/deadCode/junitEntryPointCustomRunWith/src/Test.java

@@ -0,0 +1,10 @@
+@org.junit.runner.RunWith(UnresolvedRunner.class)
+public class Test {
+  public void testSmth() {}
+
+  public void setUp() {}
+
+  public void tearDown(){}
+
+  public void notATestButCanBeRunnedWithCustomRunner(){}
+}