What does this MR do?

Adds our Go guidelines to the development doc.

Related issues

Closes #54494 (closed)

Author's checklist

• Apply the correct labels and milestone
• Crosslink the document from the higher-level index: added to doc/development/README.md
• Crosslink the document from other subject-related docs: added to doc/development/contributing/style_guides.md
• Feature moving tiers? Make sure the change is also reflected in features.yml
• Correctly apply the product badges and tiers
• Port the MR to EE (or backport from CE): always recommended, required when the ee-compat-check job fails: https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/9462

Review checklist

• Your team's review (required)
• PM's review (recommended, but not a blocker) (development guidelines)
• Technical writer's review (required)
• Merge the EE-MR first, CE-MR afterwards

/label ~Documentation golang development guidelines