Display the correct Direct Connections value in Duo admin page

What does this MR do and why?

The Duo admin page (<gitlab_url>/admin/gitlab_duo) is displaying the inverse value of the "Direct Connections" status. IE, if "Direct Connections" is enabled, the admin page shows "Not enabled" and vice versa.

The change in this MR ensures that the Duo admin page is displaying the correct "Direct Connections" status

References

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• GitLab Duo overview in admin area is always wro... (#510766 - closed)

MR acceptance checklist

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Screenshots or screen recordings

Before

See screenshots in issue GitLab Duo overview in admin area is always wro... (#510766 - closed)

After

Direct Connections enabled

Direct Connections disabled

How to set up and validate locally

1. Enable Duo Code Suggestions on your GDK

2. As the admin user (root), go to the Duo Admin page

   Navigate to Admin Area -> GitLab Duo or <gitlab_url>/admin/gitlab_duo

3. Confirm that "Direct Connections" status is displayed correctly. (See screenshots above.)

Related to #510766 (closed)