Bump omnibus-software from c155758 to a6beb05 in /omnibus

Bumps [omnibus-software](https://github.com/chef/omnibus-software) from `c155758` to `a6beb05`.
- [Release notes](https://github.com/chef/omnibus-software/releases)
- [Commits](chef/omnibus-software@c155758...a6beb05)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

omnibus/Gemfile.lock

@@ -1,6 +1,6 @@
 GIT
   remote: https://github.com/chef/omnibus-software.git
-  revision: c1557585f37c9e91466c9144dec370e983348876
+  revision: a6beb05a45db32678ce59c5d9a949995036cda83
   branch: master
   specs:
     omnibus-software (4.0.0)