Use docker pull in staging

Currently staging deployment is not checking out to new branch for new changes to be updated. Since we are using --build option which compiles all docker images in the server we need to switch to $CI_COMMIT_BRANCH for changes to be updated. Instead of doing --hard reset and clean, we can rm -rf repo and clean install it with required branch

Steps to test:

1. Create a new branch based on this branch
2. Make some visible changes in the repo
3. Protect the branch and allow it deploy to spot.eeo.one
4. Confirm that all changes are visible in spot.eeo.one ✅

/cc @arnauvp