Fix Roles API test failures

[john-odonnell]

Desired Outcome

Fix the OpenAPI description CI build.

Implemented Changes

• Remove 403 responses, and tests confirming them, from the Roles API. See Add Role and Resource lookup to Roles Controller conjur#2755.
• Update list of admin user system memberships.

Connected Issue/Story

CNJR-1816

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merged.

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Behavior

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[john-odonnell]

Tried and failed to fix the Kong example - we shouldn't let it block this PR. See my in-progress fix on the kong-fix branch.

Part of the issue is that the insomnia-inso npm package used to generate the Kong declarative config has been deprecated in favor of a new Inso CLI.

Once these are swapped, there's another issue when trying to make requests to Conjur through the Kong gateway:

<header>
  <h1>Blocked host: kong</h1>
</header>
<div id="container">
  <h2>To allow requests to kong make sure it is a valid hostname (containing only numbers, letters, dashes and dots), then add the following to your environment configuration:</h2>
  <pre>config.hosts &lt;&lt; "kong"</pre>
</div>

This is a result of Rails's Host Authorization middleware active in Conjur, restricting the set of accepted hostnames to only those listed here. Maybe we could open up the set of accepted hosts in Conjur's development config env.

[gl-johnson]

LGTM