@RunWith(SpringRunner.class)
@ActiveProfiles("test")
@SpringBootTest(classes = {ConfigurableEnvironment.class, SecurityContextUtils.class})
@WebAppConfiguration
public class ConfigurationControllerImplTest {

    private MockMvc mockMvc;

    @Autowired
    private ConfigurableEnvironment environment;

    @Autowired
    private SecurityContextUtils securityContextUtils;

    @Before
    public void setup() throws Exception {
      mockMvc = MockMvcBuilders.standaloneSetup(new  ConfigurationControllerImpl(environment, securityContextUtils)).build();
    }

    @Test
    public void getConfigField() throws Exception {
            mockMvc.perform(MockMvcRequestBuilders.post("/v1/conf/app/prop1")).andExpect(status().isOk());
    }
}

---
wo:
    ui.config.wo:
    path: "file:/conf.json"

spring:
   profiles: test