docs: added conventional commit docs

CONTRIBUTING.md

@@ -72,7 +72,7 @@ Here is a quick tip to squash all commits for a branch named `test`:
 
 ```
 git checkout test
-git reset $(git merge-base $CI_DEFAULT_BRANCH $(git rev-parse --abbrev-ref HEAD))
+git reset $(git merge-base master $(git rev-parse --abbrev-ref HEAD))
 git add -A
 git commit -m \"feat: example conventional commit\"
 git push --force