[IR] Don't print multifile/synthetic facade class names in irText tests

This only applies to JVM and fq-names in declaration references
in IR dumps.

This enables us to run more irText tests on platforms other than JVM
(see KT-58605).

compiler/testData/ir/irText/classes/initValInLambda.kt

@@ -1,6 +1,4 @@
 // FIR_IDENTICAL
-// IGNORE_BACKEND: JS_IR
-// IGNORE_BACKEND: JS_IR_ES6
 
 class TestInitValInLambdaCalledOnce {
     val x: Int