[FIR] Fix handling of type parameters in FIR mangling

#KT-57429 Fixed

compiler/testData/ir/irText/declarations/contextReceivers/fromKEEP/compareTo.kt

@@ -1,9 +1,6 @@
 // !LANGUAGE: +ContextReceivers
 // IGNORE_BACKEND: JS_IR
 
-// MUTE_SIGNATURE_COMPARISON_K2: ANY
-// ^ KT-57429
-
 data class Pair<A, B>(val first: A, val second: B)
 
 context(Comparator<T>)

compiler/testData/ir/irText/declarations/contextReceivers/genericOuterClass.kt

@@ -1,9 +1,6 @@
 // FIR_IDENTICAL
 // !LANGUAGE: +ContextReceivers
 
-// MUTE_SIGNATURE_COMPARISON_K2: JVM_IR
-// ^ KT-57429
-
 context(T) class A<T>
 
 context(Collection<P>) class B<P>

compiler/testData/ir/irText/declarations/contextReceivers/thisWithCustomLabel.kt

@@ -1,9 +1,6 @@
 // FIR_IDENTICAL
 // !LANGUAGE: +ContextReceivers
 
-// MUTE_SIGNATURE_COMPARISON_K2: JVM_IR
-// ^ KT-57429
-
 class A<T>(val a: T)
 class B(val b: Any)
 class C(val c: Any)