Add Gitea 1.18.0 upgrade information

src/hosting/gitea.md

@@ -250,6 +250,25 @@ Gitea LFS config also updated:
 	- Should be active (running).
 13. After some period of time, delete the backup file.
 
+#### Updating 1.17.4 to 1.18.0
+1. `sudo systemctl stop gitea`
+2. `sudo su - git`
+3. `gitea dump -c /etc/gitea/app.ini -w /var/lib/gitea -t /tmp`
+4. `ls -l --block-size=M`
+	- `rm <old-backup-file>`
+	- `chmod a=r <new-backup-file>`
+5. `exit`
+6. `VERSION=1.18.0`
+7. `sudo wget -O gitea https://dl.gitea.io/gitea/${VERSION}/gitea-${VERSION}-linux-amd64`
+8. `sudo systemctl status gitea`
+	- Should be inactive/dead.
+9. `sudo mv gitea /usr/local/bin/gitea`
+10. `sudo chmod +x /usr/local/bin/gitea`
+11. `sudo systemctl restart gitea`
+12. `sudo systemctl status gitea`
+	- Should be active (running).
+13. After some period of time, delete the backup file.
+
 ### Regular backups
 On the server:
 ```bash
@@ -269,3 +288,9 @@ On your local machine:
 # Copy the file locally.
 scp <user>@<remote_ip>:/home/git/<backup-file> d:\
 ```
+
+### Useful commands
+```bash
+# View Gitea disk usage.
+sudo du -sh /var/lib/gitea
+```