FIR: rename AMBIGUITY to OVERLOAD_RESOLUTION_AMBIGUITY to match FE 1.0

compiler/testData/diagnostics/tests/overload/EmptyArgumentListInLambda.fir.kt

@@ -4,5 +4,5 @@ fun foo(g: () -> Int) {}
 fun foo(f: (Int) -> Int) {}
 
 fun test() {
-    <!AMBIGUITY!>foo<!> { -> 42 }
+    <!OVERLOAD_RESOLUTION_AMBIGUITY!>foo<!> { -> 42 }
 }

compiler/testData/diagnostics/tests/overload/defaultParameters.fir.kt

@@ -55,5 +55,5 @@ fun test() {
 
     withGenericDefaults("")
 
-    <!AMBIGUITY!>wrong<!>(null!!)
+    <!OVERLOAD_RESOLUTION_AMBIGUITY!>wrong<!>(null!!)
 }

compiler/testData/diagnostics/tests/overload/disambiguateByFailedAbstractClassCheck.fir.kt

@@ -1,34 +0,0 @@
-// !WITH_NEW_IFERENCE
-// !LANGUAGE: +NewInference
-// !DIAGNOSTICS: -UNUSED_PARAMETER
-
-// FILE: packageA.kt
-
-package a
-
-abstract class Cls
-abstract class Cls2
-
-// FILE: packageB.kt
-
-package b
-
-fun Cls() {}
-class Cls2
-
-// FILE: test.kt
-
-package c
-
-import a.*
-import b.*
-
-fun take(arg: Any) {}
-
-fun test() {
-    <!AMBIGUITY!>Cls<!>()
-    take(<!AMBIGUITY!>Cls<!>())
-
-    <!UNRESOLVED_REFERENCE!>Cls2<!>()
-    take(<!UNRESOLVED_REFERENCE!>Cls2<!>())
-}

compiler/testData/diagnostics/tests/overload/disambiguateByFailedAbstractClassCheck.kt

@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 // !WITH_NEW_IFERENCE
 // !LANGUAGE: +NewInference
 // !DIAGNOSTICS: -UNUSED_PARAMETER

compiler/testData/diagnostics/tests/overload/kt2493.fir.kt

@@ -16,5 +16,5 @@ class C: A, B
 fun main() {
     AImpl().f()
     BImpl().f()
-    C().<!AMBIGUITY!>f<!>()
+    C().<!OVERLOAD_RESOLUTION_AMBIGUITY!>f<!>()
 }