Fixed a library issue where the value could not be empty

.docker/docker-compose.yml

.docs/changelog.md

dbrepo-analyse-service/Pipfile.lock

dbrepo-analyse-service/lib/dbrepo-1.9.0-py3-none-any.whl

dbrepo-analyse-service/lib/dbrepo-1.9.0.tar.gz

dbrepo-dashboard-service/Pipfile.lock

dbrepo-dashboard-service/lib/dbrepo-1.9.0-py3-none-any.whl

dbrepo-dashboard-service/lib/dbrepo-1.9.0.tar.gz

...at/ac/tuwien/ifs/dbrepo/endpoints/IdentifierEndpoint.java

...est/java/at/ac/tuwien/ifs/dbrepo/config/RabbitConfig.java

...wien/ifs/dbrepo/endpoints/IdentifierEndpointUnitTest.java

...at/ac/tuwien/ifs/dbrepo/gateway/OrcidGatewayUnitTest.java

...a/at/ac/tuwien/ifs/dbrepo/gateway/RorGatewayUnitTest.java

...wien/ifs/dbrepo/service/BrokerServiceIntegrationTest.java

...epo/service/DataCiteIdentifierServicePersistenceTest.java

.../ifs/dbrepo/service/IdentifierServicePersistenceTest.java

...rc/test/java/at/ac/tuwien/ifs/dbrepo/utils/AmqpUtils.java

...est/java/at/ac/tuwien/ifs/dbrepo/utils/KeycloakUtils.java

...ce/rest-service/src/test/resources/application.properties

...in/java/at/ac/tuwien/ifs/dbrepo/config/GatewayConfig.java