JVM IR: Remove remains of 1.2 coroutines from tests

Remove CoroutineAdapter and LANGUAGE: +ReleaseContinuation,
which are meaninless now.
Update the tests accordingly.

compiler/testData/codegen/bytecodeText/boxing/crossinlineSuspend.kt

@@ -1,5 +1,3 @@
-// !LANGUAGE: +ReleaseCoroutines
-
 inline fun inlineMe(crossinline c: suspend () -> Int): suspend () -> Int {
     val i: suspend () -> Int = { c() + c() }
     return i

compiler/testData/codegen/bytecodeText/boxing/inlineSuspend.kt

@@ -1,5 +1,3 @@
-// !LANGUAGE: +ReleaseCoroutines
-
 inline suspend fun inlineMe() = 1000
 
 // inlineMe$$forInline : valueOf

compiler/testData/codegen/bytecodeText/boxing/suspend.kt

@@ -1,5 +1,3 @@
-// !LANGUAGE: +ReleaseCoroutines
-
 suspend fun produce(): Int = 1000
 
 // 0 valueOf