TBR: Remove .v23 from .gitignore

Change-Id: Id05d7dd56007599bb76817d43f0b190c19105f97
diff --git a/.gitignore b/.gitignore
index 5e2e933..4209dc0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1 @@
 /.jiri
-#TODO(nlacasse): Get rid of .v23 below once v23->jiri transition is complete.
-/.v23