[lib] Add test of ENS avatar set to NFT which is an SVG data URI
Summary:
This is a pretty complicated and ethers.js seems to handle it perfectly!
Note that I have some long lines here... with the data URI I don't think it really matters, and with the test declarations I figured they were more readable on one line. Can change either if preferred.
Depends on D7045
Test Plan:
- Test plan described here, implemented via unit tests in this and preceding diffs
- Tested SVGs in React Native as noted here
Reviewers: atul
Reviewed By: atul
Subscribers: tomek
Differential Revision: https://phab.comm.dev/D7046