[e.cash] Reduce animation file sizes

Summary: Used a tool to optimize the lottie animations. Reduced the file sizes by quite a bit

Test Plan: preview the site and check animations still look good

Reviewers: #bitcoin_abc, bytesofman

Reviewed By: #bitcoin_abc, bytesofman

Subscribers: bytesofman

Differential Revision: https://reviews.bitcoinabc.org/D14252