Updated bundle identifiers for the app as well as unit and UI tests targets and also, improved the folder structure for the app target.

UnitTests/TodosTests.swift

@@ -0,0 +1,9 @@
+import Testing
+
+struct TodosTests {
+
+    @Test func example() async throws {
+        // Write your test here and use APIs like `#expect(...)` to check expected conditions.
+    }
+
+}