IPyWidget functional flake tests failing on and off

[IanMatthewHuff]

Here is a selection from 5 days of runs. Pretty much never the same failures two days in a row, Mac never fails and only sometimes Linux.

[rchiodo]

We can just move to just Mac only if they are consistently passing. Not likely we'll go back and work on these for Windows/Linux only

[rchiodo]

When changing this, make this only apply for the CI machine as devs will need to run them.

[rchiodo]

Going to disable ipywidget tests with jupyter server

[IanMatthewHuff]

Validated. No widget failures on most recent test runs.