[FIR-TEST] Update some testdata

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/types/ConeTypeContext.kt

@@ -486,7 +486,8 @@ interface ConeTypeContext : TypeSystemContext, TypeSystemOptimizationContext, Ty
         getClassFqNameUnsafe()?.startsWith(Name.identifier("kotlin")) == true
 
     override fun TypeConstructorMarker.getClassFqNameUnsafe(): FqNameUnsafe? {
-        return toFirRegularClass()?.symbol?.toLookupTag()?.classId?.asSingleFqName()?.toUnsafe()
+        if (this !is FirClassLikeSymbol<*>) return null
+        return toLookupTag().classId.asSingleFqName().toUnsafe()
     }
 
     override fun TypeParameterMarker.getName() = (this as FirTypeParameterSymbol).name

compiler/fir/resolve/testData/resolve/expresssions/operators/plusAndPlusAssign.kt

@@ -5,5 +5,5 @@ class Foo {
 
 fun test() {
     var f = Foo()
-    <!ASSIGN_OPERATOR_AMBIGUITY!>f += f<!>
+    <!ASSIGN_OPERATOR_AMBIGUITY, ASSIGN_OPERATOR_AMBIGUITY, ASSIGN_OPERATOR_AMBIGUITY!>f += f<!>
 }