docs: self-hosted database has timezone set to utc (supabase#40200)

Author: aantti

apps/docs/content/guides/database/postgres/configuration.mdx

@@ -20,13 +20,7 @@ This data can further be used in conjunction with the [`explain`](https://www.po
 
 ## Managing timezones
 
-Every hosted Supabase database is set to UTC timezone by default. We strongly recommend keeping it this way, even if your users are in a different location. This is because it makes it much easier to calculate differences between timezones if you adopt the mental model that everything in your database is in UTC time.
-
-<Admonition type="tip">
-
-On self-hosted databases, the timezone defaults to your local timezone. We recommend [changing this to UTC](/docs/guides/database/postgres/configuration#change-timezone) for the same reasons.
-
-</Admonition>
+Every Supabase database is set to UTC timezone by default. We strongly recommend keeping it this way, even if your users are in a different location. This is because it makes it much easier to calculate differences between timezones if you adopt the mental model that everything in your database is in UTC time.
 
 ### Change timezone