Add Go guidelines to developer docs

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

doc/development/go_guide/index.md

@@ -30,6 +30,24 @@ Reviewers and maintainers should pay attention to:
 
 TODO: Give examples
 
+### Security
+
+Security is our top-priority at GitLab. During code reviews, we must take care
+of possible security breaches in our code:
+
+- XSS using text/template
+- CSRF Protection using Gorilla
+- Use a Go version without know vulnerabilities
+- Don't leak secret tokens
+- SQL injections
+
+Remember to run
+[SAST](https://docs.gitlab.com/ee/user/project/merge_requests/sast.html) on
+your project, or at least the [gosec
+analyzer](https://gitlab.com/gitlab-org/security-products/analyzers/gosec).
+
+Web servers can take advantages of middlewares like https://github.com/unrolled/secure 
+
 ### Finding a reviewer
 
 Many of our projects are too small to have full-time maintainers. That's why we
@@ -83,6 +101,16 @@ Modules](https://github.com/golang/go/wiki/Modules)". It provides a way to
 define and lock dependencies for reproducible builds. It should be used
 whenever possible.
 
+### ORM
+
+We don't use ORMs at GitLab (except ActiveRecord, in Ruby on Rails of course).
+Projects can be structured with services to avoid them.
+[PQ](https://github.com/lib/pq) should be enough to interact with PostgreSQL databases.
+
+### Migrations
+
+TODO: https://github.com/db-journey/journey?
+
 ## Testing
 
 We don't use any specific framework for testing, as the standard library