Rename UseExperimental->OptIn, Experimental->RequiresOptIn in quickfix and IDE tests

idea/testData/quickfix/experimental/functionInLocalClass.kt

@@ -1,8 +1,8 @@
 // "Add '@MyExperimentalAPI' annotation to 'outer'" "true"
-// COMPILER_ARGUMENTS: -Xuse-experimental=kotlin.Experimental
+// COMPILER_ARGUMENTS: -Xopt-in=kotlin.RequiresOptIn
 // WITH_RUNTIME
 
-@Experimental
+@RequiresOptIn
 @Target(AnnotationTarget.FUNCTION)
 annotation class MyExperimentalAPI
 
@@ -17,4 +17,4 @@ class Outer {
             override fun foo<caret>() {}
         }
     }
-}
+}