docs(get-started): update generate types cmd (#389)

Author: onurusluca

docs/content/2.get-started.md

@@ -122,10 +122,10 @@ The path for the generated Supabase TypeScript definitions. The database definit
 
 ```bash
 ## Generate types from live database
-supabase gen types typescript --project-id YourProjectId > types/database.types.ts
+supabase gen types --lang=typescript --project-id YourProjectId > types/database.types.ts
 
 ## Generate types when using local environment
-supabase gen types typescript --local > types/database.types.ts
+supabase gen types --lang=typescript --local > types/database.types.ts
 ```
 
 Set to `false` to disable.