Remove unused check-gemfile script

The `BundleCheck` post-checkout hook works without this script, so it
can be removed.

Change-Id: I7bb48b78187a04b88d257c05f864d3f87f46fece
Reviewed-on: http://gerrit.causes.com/35605
Reviewed-by: Shane da Silva <shane@causes.com>
Tested-by: Shane da Silva <shane@causes.com>

Author: sds