test: add PasswordPolicyService mock to UserAPIUnitTest

- Add mock for PasswordPolicyService dependency
- Ensures UserAPI unit tests can run with password policy integration
- Prevents NullPointerException when UserAPI references passwordPolicyService

Required for testing UserAPI with the new password policy validation feature.

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

Co-Authored-By: Claude <noreply@anthropic.com>

Author: devondragon

src/test/java/com/digitalsanctuary/spring/user/api/UserAPIUnitTest.java

@@ -17,6 +17,7 @@
 import com.digitalsanctuary.spring.user.exceptions.UserAlreadyExistException;
 import com.digitalsanctuary.spring.user.persistence.model.User;
 import com.digitalsanctuary.spring.user.service.DSUserDetails;
+import com.digitalsanctuary.spring.user.service.PasswordPolicyService;
 import com.digitalsanctuary.spring.user.service.UserEmailService;
 import com.digitalsanctuary.spring.user.service.UserService;
 import com.digitalsanctuary.spring.user.test.builders.UserTestDataBuilder;
@@ -83,6 +84,9 @@ public JSONResponse handleSecurityException(SecurityException e) {
 
     @Mock
     private ApplicationEventPublisher eventPublisher;
+
+    @Mock
+    private PasswordPolicyService passwordPolicyService;
 
     @InjectMocks
     private UserAPI userAPI;