Allow authorization submit from Swagger UI documentations

What does this MR do and why?

This MR relaxes the sandbox restrictions for Swagger UI to make the authorization submit possible. Basic or key authorization is not possible now in gitlab instance.

This was fixed by adding the allow-forms to the iFrame sandbox attribute:

inspired by MR

Screenshots or screen recordings

Authorization is currently blocked with the issue:

After submit name and password credentials shall be saved:

Now it only prints error to console:

How to set up and validate locally

1. Create a newopenapi.yml
2. Submit basic or key authorization
3. Authorization should be saved

MR acceptance checklist

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• I have evaluated the MR acceptance checklist for this MR.