AP-416: Use berkeleyEduAlternateID in CAS callback

[danschmidt5189]

Updates user initialization code in the CAS callback to use the new berkeleyEduAlternateID instead of the deprecated berkeleyEduOfficialEmail. This is a one-liner change in the actual codebase, but with a few more references in the tests.

Note that I opted to completely remove references to berkeleyEduOfficialEmail, because 1) although CalNet is currently sending both, they will eventually remove it, and 2) this should minimize confusion down the road, in case a developer wonders why we reference both but only use one.

Additionally, I found it hard to test because the SERVE_TEST_UI flag / feature was broken. I've updated index.html to make that work (pinned to galc-ui@snapshot). I recognize that's not directly related to this change, however, so I'm happy to remove it.

[yzhoubk]

Tested locally, looks good!

1. Index page shows up at "http://localhost:3000"
2. Calnet login works for making print reserversion, and it redirects to GALC UI: "http://localhost:4000"

( Is it meant to redirect to "http://localhost:4000"? )

[danschmidt5189]

@yzhoubk I disabled the galc-ui dev instance running on :4000, rebuilt galc-api, and started everything back up. After doing that I'm not able to reproduce what you saw — I get redirected back to localhost:3000 as expected. Would you double-check? And if you're still seeing that behavior perhaps we could pair.

[yzhoubk]

@danschmidt5189 Just re-pulled and rebuilt, and I see the redirect to localhost:3000 on my local too.