UserServiceTest: removed unused import.

Reported by CheckStyle.

Correction for 48e66d2 commit.

No functional changes.

Author: php-coder

src/test/java/ru/mystamps/web/service/UserServiceTest.java

@@ -17,8 +17,6 @@
  */
 package ru.mystamps.web.service;
 
-import java.util.Date;
-
 import org.springframework.security.authentication.encoding.PasswordEncoder;
 
 import org.junit.Before;