Extract Function: Add backticks to non-identifiers and references originally surrounded in backticks

#KT-8192 Fixed

idea/testData/refactoring/extractFunction/parameters/misc/addPrefixToBackticks.kt

@@ -0,0 +1,12 @@
+// PARAM_TYPES: X
+// PARAM_TYPES: Y
+// PARAM_DESCRIPTOR: internal final fun X.test(): kotlin.Unit defined in Y
+// PARAM_DESCRIPTOR: internal final class Y defined in root package
+class X(val x: Int)
+
+// SIBLING:
+class Y(val y: Int) {
+    fun X.test() {
+        <selection>`x`plus y</selection>
+    }
+}