Investigate rake gitlab-db-migrate (via gdk update) failures

Overview

As per GDK Dashboard gdk update fails with different failure sources:

rake gitlab-db-migrate is most prominent with ~40% of failures.

We should inspect Sentry's attachments to spot patterns, why DB migrations fails.

Impacted categories

The following categories relate to this issue:

• 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.