Use @digitalbazaar/did-method-key@5 in the test suite

[mattcollier]

The test suite uses the v3 generate API that was removed as documented here:

https://github.com/digitalbazaar/did-method-key/blob/main/CHANGELOG.md#removed

The test suite should be adjust to use the modern APIs.

bedrock-kms-http/test/web/helpers.js

Line 50 in f4fdfe4

const didKey = await didKeyDriver.generate({seed});