Native: add debugger test for inspecting string variables

We just had no tests checking that debugger can properly show values
of string-typed variables. This commit adds such a test.

native/native.tests/testData/lldb/canInspectStrings.kt

@@ -0,0 +1,10 @@
+// KIND: STANDALONE_LLDB
+// LLDB_TRACE: canInspectStrings.txt
+fun main(args: Array<String>) {
+    val a = "string literal"
+    val b = buildString {
+        append("dynamic ")
+        append("string")
+    }
+    return
+}

native/native.tests/testData/lldb/canInspectStrings.txt

@@ -0,0 +1,6 @@
+> b main.kt:9
+> r
+> fr var
+(ObjHeader *) a = string literal
+(ObjHeader *) b = dynamic string
+> q

native/native.tests/tests-gen/org/jetbrains/kotlin/konan/blackboxtest/LldbTestGenerated.java

@@ -57,6 +57,12 @@ public class LldbTestGenerated extends AbstractNativeBlackBoxTest {
         runTest("native/native.tests/testData/lldb/canInspectClasses.kt");
     }
 
+    @Test
+    @TestMetadata("canInspectStrings.kt")
+    public void testCanInspectStrings() throws Exception {
+        runTest("native/native.tests/testData/lldb/canInspectStrings.kt");
+    }
+
     @Test
     @TestMetadata("canInspectValuesOfPrimitiveTypes.kt")
     public void testCanInspectValuesOfPrimitiveTypes() throws Exception {