Fix Jenkins build: error when retrieving API key

[john-odonnell]

What does this PR do?

Jenkins build was failing when retrieving user API keys when setting up test infra:

++ docker-compose exec -T conjur rails r 'print Credentials['\''cucumber:user:admin'\''].api_key'
+ api_key='[deprecated] Dry::Struct::Value is deprecated and will be removed in the next major version
/opt/conjur-server/app/domain/util/submodules.rb:7:in `const_get'\''
1h9spyz1y7jf2t2tfq8wx18jnmpravbbzvxfk1pt1svapqw3rasaae'

The deprecation message was being used in setup as part of the API key. While the source of this message needs to be addressed, the build can be fixed by retrieving the API keys with conjurctl instead of rails:

docker-compose exec -T conjur rails r "print Credentials['cucumber:user:admin'].api_key
 vv
docker-compose exec -T conjur conjurctl role retrieve-key cucumber:user:admin

What ticket does this PR close?

CyberArk internal issue link: ONYX-19910

Checklists

Change log

• The CHANGELOG has been updated, or
• This PR does not include user-facing changes and doesn't require a CHANGELOG update

Test coverage

• This PR includes new unit and integration tests to go with the code changes, or
• The changes in this PR do not require tests

Documentation

• Docs (e.g. READMEs) were updated in this PR, and/or there is a follow-on issue to update docs, or
• This PR does not require updating any documentation

[szh]

Nice. This seems like a cleaner way to go anyway.