Normalization of error status and code allowed values

[PedroDiez]

What type of PR is this?

• correction
• enhancement

What this PR does / why we need it:

This PR aims to define a normalization of error status and code allowed values for CAMARA APIs, by means of the use of a common chema model that can be applied for every excepction scenario.

Taking advantage of this PR also a correction is managed:

• 422 UNSUPPORTED_DEVICE_IDENTIFIERS exception renamed to 422 UNSUPPORTED_IDENTIFIER indicated in API Design guidelines is also included in CAMARA_common.yaml

• Also making exceptions alignment as per this comment in CAMARA_common.yaml. Updates in API Design guidelines Section 6.2 will be managed by #324 and #329

Which issue(s) this PR fixes:

Fixes #196

Does this PR introduce a breaking change?

• [ ] Yes
• [x] No

Special notes for reviewers:

Documentation impacted:

• API-Testing-Guidelines.md
• CAMARA_common.yaml

Once this PR is agreed (i.e. the baseline), other artifacts would have to be updated:

• notification-as-cloud-event.yaml
• event-subscription-template.yaml

We can talk this point in the next commonalities meeting (14/10) and aligned this with @bigludo7

Changelog input

Normalization of error `status` and `code` allowed values for CAMARA APIs.

Additional documentation

N/A

[PedroDiez]

PR ready for review (@patrice-conil, @eric-murray, @rartych, @shilpa-padgaonkar)