UI Tests: Enable screenshots in CI

[murog]

Description

Cypress UI Tests can generate screenshots for failing tests that are helpful for debugging. These should be pushed to storage and viewable by authors of PR's.

Expected Behavior

• Screenshots are enabled
• Screenshots are pushed to Storage Bucket
• Links to screenshots are surfaced in logs
• Screenshots are deleted on VM or CI has sufficient permission to delete screenshots on next build

Current Behavior

Screenshots are currently disabled because cypress docker container runs as root, resulting in artifacts that only root user can delete. When CI re-runs, it is unable to delete the screenshots directory from the previous build.

##[error]One or more errors occurred. (One or more errors occurred. (Access to the path '/home/user/actions-runner/_work/anthos-finance-demo/anthos-finance-demo/e2e/cypress/screenshots/login_spec.js/Bad Credentials on Form Submission -- fails with alert banner (failed).png' is denied.)) (Access to the path '/home/user/actions-runner/_work/anthos-finance-demo/anthos-finance-demo/e2e/cypress/screenshots/login_spec.js/Bad Credentials on Form Submission -- fails with alert banner (failed).png' is denied.)
##[error]Exit code 1 returned from process: file name '/home/user/actions-runner/bin.2.168.0/Runner.PluginHost', arguments 'action "GitHub.Runner.Plugins.Repository.v1_0.CheckoutTask, Runner.Plugins"'.

Possible solutions

• Run cypress as non-root
• Modify permissions on screenshots/ dir
• Move screenshots out of _work dir (temp fix, would need to be cleaned up manually)