encrypt-upload-client playwright tests hang in CI

[travis]

this started happening in mid-December - the first time we saw it was here:

https://github.com/storacha/upload-service/actions/runs/20342151489/job/58444237956

which is the commit after 6e8a285 - this commit passed cleanly but do seem to effect the specific package that seems to be hanging

for now we've disabled the "browser tests" for encrypt-upload-client in CI but it would be nice to bring this back at some point