developer-guide.md: add new section 'Unit-test writing' to all languages
New section was introduced by 9bc3a8c2. This PR add it to all languages.
also add the missing 'developer-guide.md' file in /sv
Edited by erciccione
The 17.0 major release is coming on May 16, 2024! This version brings many exciting improvements to GitLab, but also removes some deprecated features. We are introducing three breaking change windows during which we expect breaking changes to be deployed to GitLab.com. You can read more about it on our blogpost. The third breaking change window begins 2024-05-06 09:00 UTC and ends 2024-05-08 22:00 UTC.
New section was introduced by 9bc3a8c2. This PR add it to all languages.
also add the missing 'developer-guide.md' file in /sv