updating exposure and experience mgmt API spec to address issue #38 and #151

[maheshc01]

What type of PR is this?

Add one of the following kinds:

• bug
• correction
• enhancement/feature
• cleanup
• documentation
• subproject management
• tests

What this PR does / why we need it:

addresses #38 and #151 as well as fixes all linting errors

Which issue(s) this PR fixes:

Fixes #

Special notes for reviewers:

Changelog input

 release-note

Additional documentation

This section can be blank.

docs

[javierlozallu]

As was discussed in #229 and agreed at Edge Cloud meeting (21/05) documentation must be integrated in the yaml file following commonalities structure https://github.com/camaraproject/Commonalities/blob/main/documentation/API-DocumentationTemplate.md