[ALS-5539] Parameterize user register TOS acceptance

[srpiatt]

• Parameterize the TOS link on the landing page.
• Parameterize the TOS required acceptance on registration page.

Checklist:

• Have you successfully tested with your changes locally?
• Have you successfully deployed to an AWS account with your changes?

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

[srpiatt]

Reviewed in office hours, Jan 10, 2023.