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

compiler/testData/diagnostics/tests/dataFlowInfoTraversal/BinaryExpressionContainsConvention.fir.kt

@@ -0,0 +1,7 @@
+// !CHECK_TYPE
+
+fun foo(x: Number): Boolean {
+    val result = (x as Int) in 1..5
+    checkSubtype<Int>(x)
+    return result
+}