Draft: POC for loading commit details async

What does this MR do and why?

Quick POC to see if we can render commit details in plaintext async on the commits page.

Loads commit details async using the commits API (to be swapped out with GraphQL)

• ⚠️ renders the commitDetails in plaintext, it should be rendering processed markdown
• ⚠️ uses the commits API, we should use the GraphQL alternative
• ⚠️ not styled correctly

References

https://gitlab.com/gitlab-com/account-management/eastern-north-america/paycom-payroll-inc/paycom-payroll-pov/-/issues/76#note_2319893967

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