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

compiler/testData/diagnostics/testsWithStdLib/tryCatch/falseNegativeSmartcasts.fir.kt

@@ -0,0 +1,19 @@
+// !WITH_NEW_INFERENCE
+// !DIAGNOSTICS: -UNUSED_VARIABLE -UNUSED_VALUE -VARIABLE_WITH_REDUNDANT_INITIALIZER
+// Related issue: KT-28370
+
+fun test1(s1: String?) {
+    var s: String? = null
+    s = ""
+    try {
+        s = ""
+        requireNotNull(s1)
+    }
+    catch (e: Exception) {
+        return
+    }
+    finally {
+        s.length
+    }
+    s.length
+}