Merge branch 'bug_fixes_for_bupt' into 'develop'

etc/smf.conf

src/api-server/impl/SMContextsCollectionApiImpl.cpp

src/smf_app/smf_app.cpp

src/smf_app/smf_context.cpp

src/smf_app/smf_n11.cpp

src/smf_app/smf_n1_n2.cpp

src/smf_app/smf_n1_n2.hpp

src/smf_app/smf_procedure.cpp

src/test/amf/amf-api-server.cpp

src/test/amf_client/amf-client.cpp

src/test/inputs/apitest.json

src/test/inputs/apitest_full.json

src/test/inputs/pdu_session_create_request.hex

src/test/inputs/session_management_subscription.json

...mpl/SessionManagementSubscriptionDataRetrievalApiImpl.cpp

src/test/udm/udm-api-server.cpp