[TD] Mute some javac tests or update their testdata

There was a refactoring of AbstractDiagnosticsTest in 9052ef06 which
  contains bug that `setupEnvironment` for AbstractDiagnosticsTestUsingJavac
  was not called, so for last year tests `UsingJavac` had no difference
  with usual diagnostics tests which causes some contradictions in test data

compiler/testData/diagnostics/tests/valueClasses/functionsJvmSignaturesClash.fir.kt

@@ -1,3 +1,4 @@
+// !SKIP_JAVAC
 // !LANGUAGE: +InlineClasses
 // !DIAGNOSTICS: -UNUSED_PARAMETER
 
@@ -43,4 +44,4 @@ class C<TC : Number> {
     fun testNonGenericVsGeneric(x: X, y: Number) {}
     fun <T : Number> testNonGenericVsGeneric(x: X, y: T) {}
     fun testNonGenericVsGeneric(x: X, y: TC) {}
-}
+}