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

compiler/testData/diagnostics/tests/functionLiterals/kt6541_extensionForExtensionFunction.fir.kt

@@ -0,0 +1,10 @@
+// !DIAGNOSTICS: -UNUSED_PARAMETER
+
+interface Foo
+fun (Foo.() -> Unit).invoke(b : Foo.() -> Unit)  {}
+
+object Z {
+    <!INAPPLICABLE_INFIX_MODIFIER!>infix fun add(b : Foo.() -> Unit) : Z = Z<!>
+}
+
+val t2 = Z <!INAPPLICABLE_CANDIDATE!>add<!> { } { }