Add Dynatrace warning to Gitaly troubleshooting docs (!88672) · Merge requests · GitLab.org / GitLab

What does this MR do?

We have had two incidents in the last week where Dynatrace caused significant performance problems with the reference transaction hook.

Let's add a warning to the docs as this is quite difficult to hunt down.

Documentation-related MRs should be reviewed by a Technical Writer for a non-blocking review, based on Documentation Guidelines and the Style Guide.

If the content requires it, ensure the information is reviewed by a subject matter expert.
Technical writer review items:
- Ensure docs metadata is present and up-to-date.
- Ensure the appropriate labels are added to this MR.
- Ensure a release milestone is set.
- If relevant to this MR, ensure content topic type principles are in use, including:
  - The headings should be something you'd do a Google search for. Instead of Default behavior, say something like Default behavior when you close an issue.
  - The headings (other than the page title) should be active. Instead of Configuring GDK, say something like Configure GDK.
  - Any task steps should be written as a numbered list.
  - If the content still needs to be edited for topic types, you can create a follow-up issue with the docs-technical-debt label.
Review by assigned maintainer, who can always request/require the reviews above. Maintainer's review can occur before or after a technical writer review.