ci: add next.js data client e2e

[iartemiev]

Description of changes

Adds the e2e from this samples PR to the ci/cd pipeline

Description of how you validated changes

• Manually tested sample app in Chrome and FF
• Ran cypress against dev and prod build in Chrome
• Ran into issues with Cypress on FF. Seems to be related to this issue. I noticed that our other Next.js e2es only run on Chrome as well, so I'm assuming it's a known limitation. The sample works as expected when I manually exercise it in FF.

For reference, here are the warnings I see in the console when Cypress calls Auth.signIn in FF:

This does not occur when manually running the sample in FF. It logs in and sets the cookies successfully.

Checklist

• PR description included
• yarn test passes
• Tests are changed or added
• Relevant documentation is changed or added (and PR referenced)

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.