[IDEA-TESTS] Specify language version in feature-dependent tests

Some quickfixes are relying on diagnostics, that won't be reported
with new language features enabled.
`MixedNamedArgumentsInTheirOwnPosition`
`AllowBreakAndContinueInsideWhen`

idea/testData/quickfix/when/continueInWhenWithLabel.kt

@@ -1,4 +1,6 @@
 // "Add label to loop" "true"
+// LANGUAGE_VERSION: 1.3
+
 fun breakContinueInWhen(i: Int) {
     loop@ for (x in 0..10) {
         for (y in 0..10) {