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

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

@@ -0,0 +1,8 @@
+// !CHECK_TYPE
+
+fun foo(x: Number, y: String?): String {
+    val result = "abcde $x ${x as Int} ${y!!} $x $y"
+    checkSubtype<Int>(x)
+    checkSubtype<String>(y)
+    return result
+}