Remove caps in dependencies for kfp-related packages

[kevin-bates]

This pull request removes caps on jupyter_events, jsonschema, and pyyaml that were originally introduced due to kfp. Since kfp introduced artificial caps on jsonschema<4 and pyyaml<6, yet jupyter_events required jsonschema>=4 and pyyaml>=6 an impossible resolution was introduced. Fortunately, the floors imposed in jupyter_events were aggressive and we were able to contribute the necessary changes to decrease the floors of jsonschema and pyyaml to 3.2.0 and 5.3, respectively. Since those are the floors used by kfp the set of packages can be resolved.

The decrease of the floor in jsonschema was non-trivial and its evolution can be found here, if interested. jupyter_events 0.6.1 resolved #3070, but then the pyyaml resolution issue was encountered once the cap for jupyter_events was lifted. This latter issue was resolved in jupyter_events 0.6.2 - resulting in its current floor.

The update of test_requirements.txt to include pytest_jupyter was necessary to get tests to run now that #3070 is resolved. We should really be using the set of test dependencies listed in pyproject.toml and remove that file, but that's another story. At this moment the two sets of packages are in-sync.

(Note: test failures still occur due to #3072.)

Resolves: #3070

Signed-off-by: Kevin Bates kbates4@gmail.com

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[akchinSTC]

LGTM