create waiver pdf registration email

[bowenzhu1]

Notion ticket link

Registrant Experience: Generate and attach a .PDF of the waiver to the registration confirmation email

Implementation description

• Used JsPDF
• Generating PDF using HTML from Waiver page
• Created separate mock endpoints for emailing, and a placeholder button in the registration flow

Steps to test

Currently looks something like this

What should reviewers focus on?

Checklist

• My PR name is descriptive and in imperative tense
• My commit messages are descriptive and in imperative tense. My commits are atomic and trivial commits are squashed or fixup'd into non-trivial commits
• I have run the appropriate linter(s)
• I have requested a review from the PL, as well as other devs who have background knowledge on this PR or who will be building on top of this PR