Fix isKotlinFunctionWithBigArity function

fixup! Fix `isKotlinFunctionWithBigArity` function

Fix `isKotlinFunctionWithBigArity` function

Previous implementation could return false positive results, e.g. for
class named `abacaba.kotlin.Function42`

^KT-61548: Fixed


Merge-request: KT-MR-11928
Merged-by: Vladislav Grechko <Vladislav.Grechko@jetbrains.com>

compiler/testData/codegen/box/builtinStubMethods/extendJavaClasses/kt61548.kt

@@ -0,0 +1,27 @@
+// TARGET_BACKEND: JVM
+// IGNORE_LIGHT_ANALYSIS
+
+// FILE: Function42.java
+
+package abacaba.kotlin;
+
+public abstract class Function42 implements CharSequence {
+    @Override
+    public char charAt(int index) {
+        return 'a';
+    }
+}
+
+// FILE: box.kt
+
+package abacaba.kotlin
+
+abstract class KACharSequence : Function42() {
+    companion object {
+        const val x  = "OK"
+    }
+}
+
+fun box(): String {
+    return KACharSequence.x
+}