fix: warning of redundant type specification fixed

src/test/java/cz/muni/fi/pa165/icehockeymanager/services/TeamServiceImplTest.java

@@ -35,7 +35,7 @@ class TeamServiceImplTest {
 
     @Test
     public void getEmptyAllTeams() {
-        when(teamDao.readAll()).thenReturn(new ArrayList<Team>());
+        when(teamDao.readAll()).thenReturn(new ArrayList<>());
         assertThat(teamService.getAllTeams()).isEmpty();
         verify(teamDao).readAll();
     }