Drop all tests that disable features for language version less than 3

compiler/testData/codegen/bytecodeText/whenStringOptimization/nonInlinedConst.kt

@@ -1,16 +0,0 @@
-// !LANGUAGE: -InlineConstVals
-// IGNORE_BACKEND_FIR: JVM_IR
-// FIR status: don't support legacy feature
-
-const val y = "cde"
-
-fun foo(x : String) : String {
-    when (x) {
-        "abc", "${y}" -> return "abc_cde"
-        "e" + "fg", "ghi" -> return "efg_ghi"
-    }
-
-    return "other"
-}
-
-// 0 LOOKUPSWITCH