introduce parameter: respect varargs when rise conflict on params count/args count mismatch (IDEA-56024)

java/java-tests/testData/refactoring/introduceParameter/beforeIncompleteVararg.java

@@ -0,0 +1,10 @@
+class C {
+    void method(int k, String... s) {
+        System.out.println(s[<selection>k</selection>]);
+    }
+
+    {
+        method("a", "b", "c");
+        method();
+    }
+}