UPGRADING: fix typo

Author: staabm

Diff for: UPGRADING.md

@@ -9,7 +9,7 @@ PHPStan now requires PHP 7.4 or newer to run.
 
 ## Upgrading guide for end users
 
-The best way do get ready for upgrade to PHPStan 2.0 is to update to the **latest PHPStan 1.12 release**
+The best way to get ready for upgrade to PHPStan 2.0 is to update to the **latest PHPStan 1.12 release**
 and enable [**Bleeding Edge**](https://phpstan.org/blog/what-is-bleeding-edge). This will enable the new rules and behaviours that 2.0 turns on for all users.
 
 Also make sure to install and enable [`phpstan/phpstan-deprecation-rules`](https://github.com/phpstan/phpstan-deprecation-rules).