docs(dev-guide): add guideline for atomic commits to the developer guide

doc/dev-guide/src/coding-standards.md

@@ -1,4 +1,3 @@
-
 # Coding standards
 
 Generally we just follow good sensible Rust practices, clippy and so forth.
@@ -62,3 +61,8 @@ developer.
 
 These test helpers add pre-and-post logic to tests to enable the use of tracing
 inside tests, which can be helpful for tracking down behaviours in larger tests.
+
+## Atomic commits
+
+We use atomic commits across the repo. Each commit should represent a single unit of change.
+You can read more about atomic commits [here](https://www.aleksandrhovhannisyan.com/blog/atomic-git-commits).