Add role memberships endpoint

[gl-johnson]

Desired Outcome

Support the Role Membership endpoint. Default behavior should use the recursive membership method (?all), but also support direct membership only queries (?memberships).

Implemented Changes

Added the following URL template and relevant API methods to return a JSON list of role memberships:
ROLES_MEMBERSHIPS = "{url}/roles/{account}/{kind}/{identifier}?{membership}"

Connected Issue/Story

CyberArk internal issue link: ONYX-24035

Definition of Done

At least 1 todo must be completed in the sections below for the PR to be
merged.

Changelog

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  CHANGELOG update

Test coverage

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Documentation

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Behavior

• This PR changes product behavior and has been reviewed by a PO, or
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Security

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[szh]

Looks good. I just want to wait until you have a draft PR in the CLI so I can see the integration tests and verify the output is the same as in the Ruby API.

[gl-johnson]

CLI PR with integration tests

[szh]

LGTM!