Fix typo.mdx (#2447)

Added "for" in the first paragraph.

Co-authored-by: Jannik Maierhöfer <48529566+jannikmaierhoefer@users.noreply.github.com>

Author: leonardwolters

pages/handbook/chapters/customers.mdx

@@ -4,7 +4,7 @@ title: Who are our customers?
 
 # Who are our customers?
 
-We are building Langfuse **engineering teams working on impactful AI applications/features** that are core to their product strategy, constantly iterating and working around model limitations.
+We are building Langfuse for **engineering teams working on impactful AI applications/features** that are core to their product strategy, constantly iterating and working around model limitations.
 
 We are working with 10s of thousands of engineers and companies across industries, AI use cases, company sizes and geographies.