Restore note about @deno-types (#1256)

Co-authored-by: Luca Casonato <[email protected]>
Co-authored-by: Jo Franchetti <[email protected]>

runtime/reference/ts_config_migration.md

@@ -275,9 +275,12 @@ When you’re performing type checking on `coolLib` and using it in your file, t
 TypeScript type definitions from `coolLib.d.ts` will take precedence over
 examining the JavaScript file.
 
-The compiler hint pattern-matching is quite flexible, it accepts both quoted and
-non-quoted values for the specifier, as well as any whitespace around the equals
-sign.
+:::note
+
+In the past the `@ts-types` directive was called `@deno-types`. This alias still
+works, but is not recommended anymore. Use `@ts-types`.
+
+:::
 
 ## Providing types when hosting