Audit and update buttons on Projects::CommitsController#show

What does this MR do?

Audits button styles to ensure alignment with Pajamas. In this MR only the spacing will be updated.

As mentioned in the related issue, it’s odd that the feed button is only present for larger breakpoints, but that could be investigated separate from this effort.

Screenshots)

Before	After

Does this MR meet the acceptance criteria?

Conformity

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Availability and Testing

N/A

Security

N/A

Related to #273300 (closed)