Assume that the update_now_button will be present by default

What does this MR do and why?

We have a defensive check on the update_now_button - however it seems that in the general case this is excessive. We should assume that it will be okay to click the button, but if not then do a verification that the updating_button is actually clicked.

This should help avoid a 10 sec wait for the has_element? check to return false which appears to be the 'normal' case at the moment.

Screenshots or screen recordings

Screenshots are required for UI changes, and strongly recommended for all other merge requests.

How to set up and validate locally

    cd /path/to/gdk/gitlab/qa
    bundle exec rspec qa/specs/features/browser_ui/3_create/repository/push_mirroring_lfs_over_http_spec.rb qa/specs/features/browser_ui/3_create/repository/push_mirroring_over_http_spec.rb qa/specs/features/ee/browser_ui/3_create/repository/pull_mirroring_over_ssh_with_key_spec.rb

MR acceptance checklist

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