Decrease jupyter_core floor, cap nbclient for 3.7

[kevin-bates]

As discussed in #3069, conda installs of Elyra will fail because the dependency of jupyter_core >= 4.11.2 cannot be resolved. This is because conda removed support for Python 3.7 last August.

This pull request will allow for conda installations of Elyra to succeed, albeit supporting versions of jupyter_core <= 4.11.1. This change also resulted in capping nbclient <= 0.7.0 for Python 3.7 since more recent versions of nbclient require jupyter_core >= 4.12.

Resolves: #3069
Signed-off-by: Kevin Bates kbates4@gmail.com

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[akchinSTC]

We can keep this open for discussion tomorrow at scrum, and close when necessary

[lresende]

Should we just remove support for Python 3.7?

[kevin-bates]

Should we just remove support for Python 3.7?

I agree. I think the bigger question is in what release can/should this removal occur in - 3.15 or 4.0?

[kevin-bates]

We should still merge this PR since it's limiting functionality on python releases > 3.7. We can talk about dropping 3.7 independently.