Add jupyter intergration testing to CI

[kgartland-rstudio]

Description

rsconnect-jupyter uses rsconnect-python to add servers and deploy content. Due to this dependency, we've had to manually test rsconnect-jupyter for all rsconnect-python releases. This can cause delays in the release process or defects in rsconnect-jupyter if not properly tested. Adding tests in CI protects us from making breaking changes to rsconnect-jupyter. This will also set us up to test for voila mode in rsconnect-jupyter.

Motivation and Context

We've had to hold releases or release patches in the past to fix breaking changes in rsconnect-jupyter.

How Has This Been Tested?

The tests are currently passing:
https://github.com/rstudio/rsconnect-python/actions/runs/4135755212

Cypress failures cause CI to fail:
https://github.com/rstudio/rsconnect-python/actions/runs/4135608575

In the intergration-testing directory, run:
just build && just up && just up-cypress

just build build the docker images (client, cypress)
just up will start the docker images (client, connect)
just up-cypress will start the cypress docker image and run the tests.

• The client container is where rsconnect-python and rsconnect-jupyter packages are installed. rsconnect-jupyter installs on the just build command where the current dev build of rsonnect-python gets installed on the just up command so rebuilding isn't necessary to get the current rsconnect-python dev build.

• The connect container is pulled from docker hub with the latest version of Posit Connect.

• The cypress container runs cypress version 12.0.0 and tests all defined specs on the just up-cypress command.

Fixes #351

Screenshots (if appropriate):

Types of Changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• CI Changes

Checklist:

• I have added tests to cover my changes.
• I have updated CHANGELOG.md to cover notable changes.

[tdstein]

LGTM! All of my comments are minor questions.