Merge branch 'master' into mb/behat

...7/grading/moodle/api/v1/controller/GradingController.java

...s107/grading/moodle/api/v1/controller/PingController.java

...odle/api/v1/controller/RegistryCredentialsController.java

...rading/moodle/api/v1/controller/SubmissionController.java

...107/grading/moodle/api/v1/dto/DownloadCredentialsDTO.java

...s107/grading/moodle/api/v1/dto/DownloadSubmissionDTO.java

...epfl/cs107/grading/moodle/api/v1/dto/GradeRequestDTO.java

...cs107/grading/moodle/api/v1/dto/UploadCredentialsDTO.java

...7/grading/moodle/api/v1/service/KubernetesJobService.java

...cs107/grading/moodle/api/v1/service/MoodleWebService.java

...ing/moodle/api/v1/service/SubmissionIntegrityService.java

.../ch/epfl/cs107/grading/moodle/logging/MdcInterceptor.java

...pfl/cs107/grading/moodle/logging/WebMvcConfiguration.java

moodle-grading-service/src/main/resources/logback-spring.xml

...l/cs107/grading/moodle/controller/PingControllerTest.java

.../cs107/grading/moodle/utils/WithApiKeyAuthentication.java

...grading-service/src/test/resources/application.properties