feat: allow filtering of enrollments in enroll:list

[srieteja]

closes https://github.com/atsign-foundation/at_server/issues/1748 - What I did

• feat: add impl to filter enrollment requests using ApprovalState
• append 'Status' to enrollment value for all enrollments listed by enroll:list (whose value will be the approval status of that enrollment)

- How I did it

• changes made in https://github.com/atsign-foundation/at_libraries/pull/530 so that enroll:list can accept verbParams (which previously it did not)
• If 'approvalStatusFilter' is passed through verbParams, enroll list compares all enrollments to this param while fetching EnrollDataStoreValue from hive. And returns the enrollments that match the status passed through verbParams

- How to verify it

• unit tests present to validate changes

- Description for the changelog

feat: allow filtering of enrollments in enroll:list

[srieteja]

Also, please add functional tests for the same.

@sitaram-kalluri functional tests have been added as part of test: add functional tests + 1 unit test