Use test path relative to testDataPath in fixture.configureByFile to be complaint with 193

idea/idea-test-framework/test/org/jetbrains/kotlin/idea/test/KotlinLightCodeInsightFixtureTestCase.kt

@@ -62,6 +62,9 @@ abstract class KotlinLightCodeInsightFixtureTestCase : KotlinLightCodeInsightFix
 
     protected open val captureExceptions = true
 
+    protected fun testPath(): String =
+        File(testDataPath, fileName()).toString()
+
     override fun setUp() {
         super.setUp()
         // We do it here to avoid possible initialization problems