Add contributor tools update instructions

Editor assessment

The subject says instructions for updating contributor tools were added to the docs, which is clear and states both the artifact and its purpose; a reader knows what the commit delivers without the diff. The chore type is defensible for documentation-adjacent maintenance, and the docs scope locates the area correctly. No body appears, and one line on what the instructions cover would have added value, but the subject carries the essential fact. The PR reference is well formed and no footers add noise. Style is clean: imperative mood, no trailing period, moderate length. Clear and honest with a modest thinness.