docs: add timezone configuration instructions to manual installation guide

- Included a new environment variable, TZ, for setting the timezone in Dokploy installations.
- Added a section detailing how to update the timezone using a Docker command, enhancing user guidance for server configuration.

Fix this question Dokploy/dokploy#2688

Author: Siumauricio

apps/docs/content/docs/core/manual-installation.mdx

@@ -12,6 +12,7 @@ If you wish to customize the Dokploy installation on your server, you can modify
 5. **RELEASE_TAG** - Set to a dokploy docker hub tag(latest, canary, feature, etc)
 6. **DATABASE_URL** - Set to another database url if you want to use a different database.
 7. **REDIS_HOST** - Set to another redis url if you want to use a different redis.
+8. **TZ** - Set to another timezone if you want to use a different timezone.
 
 ## Installation Script
 
@@ -284,6 +285,16 @@ docker service create \
   dokploy/dokploy:latest
 ```
 
+## Setup Dokploy Timezone
+
+To setup the timezone of Dokploy, you can use the following command:
+
+```bash
+docker service update --env-add TZ=America/New_York dokploy
+```
+
+
+
 ## Manual Upgrade
 
 To upgrade Dokploy manually, you can use the following command: