fix: restore edgefn docs (#46399)

- closes https://github.com/supabase/supabase/issues/46397


b4: https://supabase.com/docs/guides/functions/connect-to-postgres (404)
after:
https://docs-git-fork-7ttp-fix-404-edgefn-supabase.vercel.app/docs/guides/functions/connect-to-postgres
(200)

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## Summary by CodeRabbit

* **Documentation**
* Fixed a broken snippet reference in the Drizzle guide and added a
formatting override to ensure the code sample renders correctly
(documentation-only change).

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apps/docs/content/guides/functions/connect-to-postgres.mdx

@@ -80,9 +80,10 @@ language="json"
 
 Then define your schema and query the database:
 
+{/* prettier-ignore */}
 <$CodeSample
-path="/edge-functions/supabase/functions/\_shared/schema.ts"
-title="supabase/functions/\_shared/schema.ts"
+path="/edge-functions/supabase/functions/_shared/schema.ts"
+title="supabase/functions/_shared/schema.ts"
 language="typescript"
 />