[FIR] Approximate integer constants in lhs of callable reference

compiler/fir/analysis-tests/testData/resolve/references/integerLiteralInLhs.kt

@@ -0,0 +1,9 @@
+fun Short.foo(): Int = 1
+fun Int.foo(): Int = 2
+
+fun testRef(f: () -> Int) {}
+
+fun test() {
+    // should resolve to Int.foo
+    testRef(1::foo)
+}