Reduce the use of "According to custom instructions in" in comments
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## Problem
At the moment Duo Code Review is commonly starting comments with the phrase "According to custom instructions in" but almost always when I see this the comment then goes on to describe something that it made up.
See example https://gitlab.com/gitlab-org/gitlab/-/merge_requests/196727#note_2616229084 .
Even if it was in the "custom instructions" Duo Code review is not linking to those instructions for the reader to even know what is being referred to.
I believe this statement causes more confusion.
## Solution
Either:
1. Stop adding this statement to messages
2. Add a link to the custom instructions file so the reader knows what is being referred to AND also try to ensure that Duo Code Review is actually referring to a specific instruction there
issue