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

compiler/testData/diagnostics/tests/operatorRem/preferRemAsExtentionOverMod.fir.kt

@@ -0,0 +1,13 @@
+// !LANGUAGE: -ProhibitOperatorMod
+// !DIAGNOSTICS: -UNUSED_PARAMETER
+
+class Foo {
+}
+operator fun Foo.mod(x: Int): Foo = Foo()
+operator fun Foo.rem(x: Int): Int = 0
+
+fun foo() {
+    takeInt(Foo() % 1)
+}
+
+fun takeInt(x: Int) {}