Update CLI generate test to use branch from ENV variable

[bterone]

Why

Currently, we've done a quick fix to ensure that the CI passes on every branch, however, that is not a long-term solution.

Previously the issue was that the vite template would be downloaded from the repository, however we needed to specify a branch name or a commit hash that contained the vite template folder.

A longer-term solution would be to fetch the current branch, pass that as an environment variable so the test can use that as the viteTemplateReference and pull the vite template from there.

Who Benefits?

Everyone including future contributors to the vite template package 🤗