[libc] Fix typo in buildbot README.txt.

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D90381

GitOrigin-RevId: a8beb4ada4bd01980e9effc8a2671d4c6454a7ba
diff --git a/utils/buildbot/README.txt b/utils/buildbot/README.txt
index 3edec0e..40c2cb5 100644
--- a/utils/buildbot/README.txt
+++ b/utils/buildbot/README.txt
@@ -1,5 +1,5 @@
 This folder contains resources needed to create a docker container for
-llvm-libc builbot worker.
+llvm-libc buildbot worker.
 
 Dockerfile: Sets up the docker image with all pre-requisites.