Fix issue not passing Dast::Profile branch

What does this MR do?

fixes a regression introduced by !56821 (merged).

Why?

dast on-demand scans will run against the project's default branch rather than the one set in dast_profile.

the reason this happened is that there are two features that are slightly out of alignment sharing code and i missed this detail when ensuring one of our services supported both features.

Screenshots (strongly suggested)

Maintainer

demonstration that the refs match.

Developer

demonstration that a developer may run a scan on a non-protected ref.

Does this MR meet the acceptance criteria?

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