CI: integ tests for Brazil workspaces

## Problem

During each Amazon Q release, the testgen team needs to manually test the plugin against Brazil workspaces as this is the majority of where bugs are. Adding automated Brazil workspace testing support (either through e2e tests or other means) would help us reduce weekly manual testing effort and accelerate the release verification process.

While a brazil workspaces could be added to testFixtures in toolkit repo, it can be huge and it would add a ton of unnecessary files to testFixtures. It also doesn't feel right to include details about internal repos in the toolkit repo.

## Expected behavior
Support automated Brazil workspace testing support in some means

Start by reviewing the repository’s existing integration and e2e test setup, then inspect how testFixtures are organized. The issue does not name specific files or entry points, so first determine where workspace fixtures and release verification tests belong. Done means Brazil workspace testing runs automatically without adding internal repository details or a large fixture tree to testFixtures.

Written by the indexing model from the issue text.