KT-33372 Remove renaming file reference to the contents of the file

- There is still a hack with returning null from `getLastFileReference`,
it is here to keep KT-25674 issue fixed
- Overrides of `bindToElement` are removed, they caused renames of the
file references to their contents
- Code of `KotlinFilePathReferenceContributor.kt` is refactored
- ^KT-33372 ^KT-32514 ^KT-36306 Fixed

idea/testData/refactoring/rename/renameReferencedResourceFile/before/main.kt

@@ -0,0 +1,6 @@
+fun take(a: String) {}
+
+fun usage() {
+    take("resource.txt")
+    take("./resource.txt")
+}

idea/testData/refactoring/rename/renameReferencedResourceFile/before/resource.txt

@@ -0,0 +1 @@
+resource content