K2: Fix false-negative RETURN_TYPE_MISMATCH

^KT-53987 Fixed
^KT-55932 Fixed

compiler/fir/analysis-tests/testData/resolve/diagnostics/returnTypeMismatchOnOverride.fir.txt

@@ -180,7 +180,7 @@ FILE: returnTypeMismatchOnOverride.kt
         }
 
         public open fun kek(): R|Z| {
-            ^kek R|/Z.Z<CS errors: /Z.Z>#|()
+            ^kek R|/Z.Z|()
         }
 
     }

compiler/fir/analysis-tests/testData/resolve/extendedCheckers/canBeReplacedWithOperatorAssignment/mutableList.fir.txt

@@ -1,5 +1,5 @@
 FILE: mutableList.kt
     public final fun foo(): R|kotlin/Unit| {
         lvar listVar: R|kotlin/collections/MutableList<kotlin/Int>| = R|kotlin/collections/mutableListOf|<R|kotlin/Int|>(vararg(Int(1), Int(2), Int(3)))
-        R|<local>/listVar| = R|<local>/listVar|.R|kotlin/collections/plus<CS errors: kotlin/collections/plus>#|<R|kotlin/Int|>(Int(4))
+        R|<local>/listVar| = R|<local>/listVar|.R|kotlin/collections/plus|<R|kotlin/Int|>(Int(4))
     }

compiler/fir/analysis-tests/testData/resolve/kt54775.kt

@@ -2,7 +2,6 @@ fun <T> bar(): T {
     return null <!UNCHECKED_CAST!>as T<!>
 }
 
-class X() : <!UNRESOLVED_REFERENCE, UNRESOLVED_REFERENCE!>B<!> by <!ASSIGNMENT_IN_EXPRESSION_CONTEXT!><!VARIABLE_EXPECTED!><!UNRESOLVED_REFERENCE!>get<!>()<!> = bar()<!> {
+class X() : <!UNRESOLVED_REFERENCE, UNRESOLVED_REFERENCE!>B<!> by <!ASSIGNMENT_IN_EXPRESSION_CONTEXT!><!VARIABLE_EXPECTED!><!UNRESOLVED_REFERENCE!>get<!>()<!> = <!NEW_INFERENCE_NO_INFORMATION_FOR_PARAMETER!>bar<!>()<!> {
     val prop = <!ASSIGNMENT_IN_EXPRESSION_CONTEXT!><!VARIABLE_EXPECTED!><!NEW_INFERENCE_NO_INFORMATION_FOR_PARAMETER!>bar<!>()<!> = 2<!>
 }
-

compiler/fir/analysis-tests/testData/resolveWithStdlib/diagnostics/functionReturnTypeMismatchChecker/basic.fir.txt

@@ -20,7 +20,7 @@ FILE: basic.kt
         ^okOneLineFunction Int(10).R|kotlin/Int.plus|(Int(1))
     }
     public final fun errorOneLineFunction(): R|kotlin/String| {
-        ^errorOneLineFunction Int(10).R|kotlin/Int.plus<CS errors: kotlin/Int.plus>#|(Int(1))
+        ^errorOneLineFunction Int(10).R|kotlin/Int.plus|(Int(1))
     }
     public final class A : R|kotlin/Any| {
         public constructor(): R|A| {

compiler/fir/analysis-tests/testData/resolveWithStdlib/diagnostics/functionReturnTypeMismatchChecker/basic.kt

@@ -1,6 +1,6 @@
 // bug: type of the expression in return statement is Char
 fun illegalReturnIf(): Char {
-    return if (1 < 2) 'a' else { 1 }
+    return <!RETURN_TYPE_MISMATCH!>if (1 < 2) 'a' else { 1 }<!>
 }
 
 fun foo(): String {