Add deploy instructions

deploy/calculator.service

+Description=CiCd.
+After=network.target
+StartLimitIntervalSec=0
+
+[Service]
+Type=simple
+ExecStart=python3 -m uvicorn server:app --port 80 --host 0.0.0.0
+User=root
+WorkingDirectory=/var/www/cicd/calculator
+
+[Install]
+WantedBy=multi-user.target

deploy/setup.md

+# Setup la vm pour notre calculatrice
+
+## Clone le repo
+
+```bash
+mkdir -p /var/www
+cd /var/www
+git clone https://gitlab.viarezo.fr/<login>/cicd.git
+```
+
+## Installe les dépendances
+
+```bash
+cd cicd
+pip install -r requirements.txt
+```
+
+## Ajoute le service
+
+```bash
+cp deploy/calculator.service /etc/systemd/system/
+systemctl daemon-reload
+systemctl enable calculator
+systemctl start calculator
+```
+
+## Dans ton navigateur
+
+- "http://ip-de-la-vm:80/"