docs(contribution): mentioning the code conventions (#640)

refactor(docs): mentioning the code conventions

Author: mfranzke

CONTRIBUTING.md

@@ -8,4 +8,8 @@ We are committed to fostering a welcoming, respectful, and harassment-free envir
 
 Please make sure that husky is installed correctly to validate your changes.
 
-Moreover, you need to duplicate ``.env.template`` as ``.env`` and type your own email address. This ensures that you have the correct email set for this project.
+Moreover, you need to duplicate ``.env.template`` as ``.env`` and type your own email address. This ensures that you have the correct email set for this project.
+
+### Conventions
+
+Please be aware that we have some [code and git commit (message and branch naming) conventions](doc/conventions.adoc), that we ensure with some linting tools.