*: Update top-level readme

Fix typo in README file name.

Change-Id: If6eeeef8b1feed1eb3d359f84adb2d043ddd9088
Reviewed-on: https://bluetooth-review.googlesource.com/c/bluetooth/+/2300
Reviewed-by: Ani Ramakrishnan <aniramakri@google.com>

docs/commit_messages.md

diff --git a/docs/commmit_messages.md b/docs/commit_messages.md
similarity index 100%
rename from docs/commmit_messages.md
rename to docs/commit_messages.md