fix(test): Fix flaky sign-in-cached functional test. (#4352)
fix(test): Fix flaky sign-in-cached functional test. (#4352)

Remove the .sleep in `sign in with desktop context then no context,
desktop credentials should not persist` and use a `visibleByQSA`
instead.
mozilla/fxa-content-server,mozilla/fxa-content-server,mozilla/fxa-content-server,shane-tomlinson/fxa-content-server,shane-tomlinson/fxa-content-server,shane-tomlinson/fxa-content-server