Fix Transmute's Interop tests

[baha-ai]

Need to replace Transmute's url as the Google web app (https://did-edv.web.app) does not work anymore

ref: w3c-ccg/did-method-web#25 for workaround

[DRK3]

Talked to Transmute - that web app is no longer available. We'll need to find another way to do interop tests.

[DRK3]

(That w3c-ccg/did-method-web#25 link is something completely unrelated - there was a miscommunication earlier, please disregard)