Update guest-configuration-custom.md

Fixed up some grammatical errors.

Author: waynehoggett

articles/governance/policy/concepts/guest-configuration-custom.md

@@ -55,9 +55,9 @@ extracted.
 
 Multiple benefits result from this change.
 
-- It's possible to use difference module versions for each configuration, on
+- It's possible to use different module versions for each configuration, on
   the same machine.
-- When a configuration is no longer deleted on a machine, the entire folder
+- When a configuration is no longer needed on a machine, the entire folder
   where it was extracted is safely deleted by the agent without the need to
   manage shared dependencies across configurations.
 - It's not required to manage multiple versions of any module in a central