Run geo-install job by default

What does this merge request do and why?

• Always run geo-install job. (But still allow failure for now. Just being cautious because there were intermittent unexplained gdk start ssh errors in the original MR. Let's see if those come back or not.)
• Reuse the geo-install script in the pre-built GDK image rather than curling from somewhere else. (This resolves Error in geo-install job: "support/ci/verify-ge... (#1890 - closed))
• Reuse the pre-built GDK in the image as the primary site. (Since the point is not to test the one-line GDK install. This reduces job duration by ~20 minutes.)
• Save the secondary site logs as artifacts for better debugging
• Adds collapsible sections to geo-install job

Impacted categories

The following categories relate to this merge request:

• gdk-reliability - e.g. When a GDK action fails to complete.
• gdk-usability - e.g. Improvements or suggestions around how the GDK functions.
• gdk-performance - e.g. When a GDK action is slow or times out.

Merge request checklist

• This change is backward compatible. If not, please include steps to communicate to our users.
• Tests added for new functionality. If not, please raise an issue to follow-up.
• [-] Documentation added/updated, if needed.
• [-] Announcement added, if change is notable.
• [-] gdk doctor test added, if needed.
• [-] Add the ~highlight label if this MR should be included in the CHANGELOG.md.