KT-7716 Introduce Variable's name suggestions often have "1" at the end for no real reason

#KT-7716 Fixed

idea/testData/refactoring/introduceVariable/NameSuggestionBug.kt

@@ -0,0 +1,8 @@
+class For
+
+val For.parent: For
+    get() = For()
+
+fun foo(f: For) {
+    <selection>f.parent</selection>
+}

idea/testData/refactoring/introduceVariable/NameSuggestionBug.kt.after

@@ -0,0 +1,8 @@
+class For
+
+val For.parent: For
+    get() = For()
+
+fun foo(f: For) {
+    val parent = f.parent
+}