[FIR] Fix tests (ARGUMENT_TYPE_MISMATCH instead of INCOMPATIBLE_CANDIDATE)

compiler/testData/diagnostics/tests/dataFlow/EmptyIf.fir.kt

@@ -7,14 +7,14 @@ fun f1(s: String?) {
 
 fun f2(s: Number?) {
     if (s is Int);
-    <!INAPPLICABLE_CANDIDATE!>checkSubtype<!><Int>(s)
+    checkSubtype<Int>(<!ARGUMENT_TYPE_MISMATCH!>s<!>)
     if (s as Int == 42);
     checkSubtype<Int>(s)
 }
 
 fun f3(s: Number?) {
     if (s is Int && s as Int == 42);
-    <!INAPPLICABLE_CANDIDATE!>checkSubtype<!><Int>(s)
+    checkSubtype<Int>(<!ARGUMENT_TYPE_MISMATCH!>s<!>)
 }
 
 fun f4(s: Int?) {

compiler/testData/diagnostics/tests/dataFlow/IsExpression.fir.kt

@@ -1,6 +1,6 @@
 fun f(a: Boolean, b: Int) {}
 
 fun foo(a: Any) {
-    <!INAPPLICABLE_CANDIDATE!>f<!>(a is Int, a)
+    f(a is Int, <!ARGUMENT_TYPE_MISMATCH!>a<!>)
     1 <!NONE_APPLICABLE!>+<!> a
 }