Convert Authn to frontend-base

[arbrandes]

Description

Convert the Authn MFE to use frontend-base, as per https://github.com/openedx/frontend-base/blob/main/docs/how_tos/migrate-frontend-app.md.

The converted code will remain in a long-lived frontend-base branch.

Dropped features

The following features are removed as part of the conversion:

• Zendesk (DEPR)
• Algolia (DEPR)
• Optimizely (DEPR)
• Recommendations (DEPR)
• Simplify registration experiment (DEPR)
• SHOW_CONFIGURABLE_EDX_FIELDS (DEPR)

DEPR tickets will be linked above as they're created.

PRs

• refactor: migrate to frontend-base #1512

TODO

At the time of writing the initial conversion and tests are complete. What's left is to continue rebasing/fixing on master until its time to land.

• Initial conversion
• Fix tests
• feat: Prepare for publication to NPM #1515
• Publish to NPM as a buildless library
• Include in frontend-template-site as default configuration
• Paragon 23 (depends on frontend-base support)
• Ongoing: merges with master