Remove custom role queries from Projects::JobsController#show

What does this MR do and why?

• Projects::JobsController#show gets polled every few seconds and it triggers a custom role query which isn't needed (about 1M in 24 hours).
• Remove the policy checks from RunnerEntity when returning paths which are triggering the custom role query

References

How to reproduce locally

1. Navigate to any project that you are a developer+ of
2. Go to Build > Jobs and click on any job. You shouldn't notice any change / errors.

MR acceptance checklist

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Related to #508616 (closed)