[FIR-TEST] Add new testdata generated after changes in previous commit

compiler/testData/diagnostics/tests/inner/extensionFun.fir.kt

@@ -0,0 +1,28 @@
+class Outer {
+    class Nested
+    inner class Inner
+    
+    fun Inner.foo() {
+        Outer()
+        Nested()
+        Inner()
+    }
+    
+    fun Nested.bar() {
+        Outer()
+        Nested()
+        Inner()
+    }
+    
+    fun Outer.baz() {
+        Outer()
+        Nested()
+        Inner()
+    }
+}
+
+fun Outer.foo() {
+    Outer()
+    Nested()
+    Inner()
+}