Add upgrade guide section to webiste (#6294)

...to guide user to transition between versions.

---------

Co-authored-by: Félix Malfait <felix.malfait@gmail.com>

packages/twenty-website/src/content/developers/constants/DocsIndex.ts

@@ -6,6 +6,7 @@ export const DOCS_INDEX = {
       { fileName: 'self-hosting-var' },
       { fileName: 'docker-compose' },
       { fileName: 'cloud-providers' },
+      { fileName: 'upgrade-guide' },
     ],
   },
   Extending: {

packages/twenty-website/src/content/developers/self-hosting/upgrade-guide.mdx

@@ -0,0 +1,37 @@
+---
+title: Upgrade guide
+icon: TbCloud
+image: /images/user-guide/notes/notes_header.png
+---
+
+## General guidelines 
+
+Always make sure to backup your database before starting the upgrade process.
+
+## If you used Docker Compose
+
+1. In a terminal, on the host where Twenty is running, turn off Twenty: `docker compose down`
+
+2. Upgrade the version by changing the `TAG` value in the .env file near your docker-compose.
+
+3. Bring Twenty back online with `docker-compose up -d`
+ 
+## Data Migration
+
+Migrating a CRM is a bit trickier than migrating a traditional software, because the data model of Standard Object has to evolve smoothly along your custom objects.
+
+## v0.21.0 to v0.22.0
+
+Run the following commands:
+
+```
+yarn database:migrate:prod 
+yarn command:prod workspace:sync-metadata -f 
+yarn command:prod upgrade-0.22
+```
+
+The `yarn database:migrate:prod` command will apply the migrations to the Database.  
+The `yarn command:prod workspace:sync-metadata -f` command will sync the definition of standard objects to the metadata tables and apply to required migrations to existing workspaces.  
+The `yarn command:prod upgrade-0.22` command will apply specific data transformations to adapt to the new object defaultRequestInstrumentationOptions.
+
+<ArticleEditContent></ArticleEditContent>