[Copilot] Change references from "tomls/base/main" branch to "4.0" branch

[christopherco]

Issue Description

Find all the references in this repository to the "tomls/base/main" git branch in azurelinux repository and point them to the "4.0" branch

Expected Changes

All mention of "tomls/base/main" should be changed to "4.0".
There should be no remaining references to "tomls/base/main".

Additional Context

No response