Remove LANGUAGE_VERSION from non-coroutine codegen tests

Most of these tests used this directive as a way to opt in to a new
language feature, and most of those features are already stable for a
long time, so no opt-in is needed. Some other tests used the directive
to opt out from a language feature, replace those by the `LANGUAGE`
directive. One test used the directive to test behavior that actually
depended on the API version; use `API_VERSION` directive there instead.

compiler/testData/codegen/asmLike/receiverMangling/deepNoinlineWithLabels_after.kt

@@ -1,5 +1,5 @@
+// !LANGUAGE: +NewCapturedReceiverFieldNamingConvention
 // LOCAL_VARIABLE_TABLE
-// LANGUAGE_VERSION: 1.3
 
 fun String.foo(count: Int) {
     val x = false
@@ -15,4 +15,4 @@ fun String.foo(count: Int) {
     }
 }
 
-fun block(block: Long.() -> Unit) = 5L.block()
+fun block(block: Long.() -> Unit) = 5L.block()