Tests: remove JVM diagnostics from AbstractDiagnosticsTest

There's no behavior specific for JVM backend diagnostics in any of the
affected tests, and this code is using an incorrect way to obtain those
diagnostics, so it should be removed anyway.

compiler/tests/org/jetbrains/kotlin/checkers/InteropFunctionsWithNonStableParameterNamesDiagnosticsTest.kt

@@ -43,8 +43,6 @@ class InteropFunctionsWithNonStableParameterNamesDiagnosticsTest : AbstractDiagn
         klibFile = prepareKlibWithNonStableParameterNames(tmpDir)
     }
 
-    override fun shouldSkipJvmSignatureDiagnostics(groupedByModule: Map<TestModule?, List<TestFile>>) = true
-
     override fun getEnvironmentConfigFiles(): EnvironmentConfigFiles = EnvironmentConfigFiles.METADATA_CONFIG_FILES
 
     override fun createModule(moduleName: String, storageManager: StorageManager): ModuleDescriptorImpl =
@@ -129,4 +127,3 @@ class InteropFunctionsWithNonStableParameterNamesDiagnosticsTest : AbstractDiagn
 
     }
 }
-