Migrate Usage Quotas spec to MSW

What does this MR do and why?

Migrates the usage quotas spec to MSW and requests test to address current timing and flakiness issues

References

• Flaky test issue: https://gitlab.com/gitlab-org/quality/test-failure-issues/-/work_items/44876+
• Epic to migrate to MSW: Migrate Verify domain Capybara to MSW (#625161 - closed)

Screenshots or screen recordings

N/A

Metrics

Current Average (Capybara)	This MR
	7 seconds

Grafana Dashboard link

How to set up and validate locally

1. Generate the fixtures:

bundle exec rspec ee/spec/frontend/fixtures/usage_quotas_integration.rb

2. Run the MSW tests

yarn jest:integration ee/spec/frontend/integration/usage_quotas/pipelines_spec.js

MR acceptance checklist

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