Fix: Tweak intro sentence.

As per Yuji's comment on previous PR.

Author: kateandrews

docs/how-to/lock-contexts-with-clerk.md

@@ -1,7 +1,7 @@
 
 # Locking context with Next.js and Clerk
 
-This how-to guide shows you how to lock context if you're using [Clerk](https://clerk.com/) with Next.js.
+This how-to guide shows you how to use lock context if you're using [Clerk](https://clerk.com/) with Next.js.
 
 ## Table of contents