* fix: do not send internal logs on server errors

- catch specific 5xx errors and don't send entire error string
in API response

Signed-off-by: Atul Kumar <Atul.Kumar@fujitsu.com>

* feat: implement endorsements lifecycle mgmt. API

This PR implements the REST API endpoints and handlers for activation
and deactivation of endorsement triples as specified by the spec
(See
https://github.com/veraison/docs/blob/main/api/endorsement-provisioning/endorsement-provisioning.yaml).

- update some copyrights
- use application/concise-problem-details+cbor
- add integration-tests

Signed-off-by: Kumar, Atul <Atul.Kumar@fujitsu.com>

---------

Signed-off-by: Atul Kumar <Atul.Kumar@fujitsu.com>
Signed-off-by: Kumar, Atul <Atul.Kumar@fujitsu.com>
Co-authored-by: Atul Kumar <Atul.Kumar@fujitsu.com>