Maintenance: ControllerAdviceTest - Add missing @UnitTest annotation

Added @UnitTest annotation to ControllerAdviceTest to ensure it's properly
categorized and can be run with the unitTest Gradle task.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <[email protected]>

Author: github-actions[bot]

src/test/java/spring/memewikibe/api/controller/ControllerAdviceTest.java

@@ -12,6 +12,7 @@
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RestController;
+import spring.memewikibe.annotation.UnitTest;
 import spring.memewikibe.support.error.ErrorType;
 import spring.memewikibe.support.error.MemeWikiApplicationException;
 import spring.memewikibe.support.response.ApiResponse;
@@ -20,6 +21,7 @@
 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
 
+@UnitTest
 class ControllerAdviceTest {
 
     private MockMvc mockMvc;