Requiring Python >=3.8 enables walrus operator

[dbeatty10]

resolves #849
docs N/A

Problem & Solution

The problem and solution are explained clearly in #849

Checklist

• I have read the contributing guide and understand what's expected of me
• I have run this code in development and it appears to resolve the stated issue
• This PR includes tests, or tests are not required/relevant for this PR
• This PR has no interface changes (e.g. macros, cli, logs, json artifacts, config files, adapter interface, etc)

[dbeatty10]

Could we backport this as well?

[mikealfare]

Could we backport this as well?

Agreed. We need to backport it all the way since py37 is EOL and no longer supported.

[mikealfare]

@dbeatty10, do you mind updating the comment at the top of setup.py as well? It doesn't do anything, but if we're updating this, we might as well do both.

[dbeatty10]

@dbeatty10, do you mind updating the comment at the top of setup.py as well? It doesn't do anything, but if we're updating this, we might as well do both.

I updated the comment to be evergreen:

- # require python 3.7 or newer
+ # require a supported version of Python

[github-actions]

The backport to 1.0.latest failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-1.0.latest 1.0.latest
# Navigate to the new working tree
cd .worktrees/backport-1.0.latest
# Create a new branch
git switch --create backport-852-to-1.0.latest
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 4368ef497d05e6069b4b45ea100d4258536e9521
# Push it to GitHub
git push --set-upstream origin backport-852-to-1.0.latest
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-1.0.latest

Then, create a pull request where the base branch is 1.0.latest and the compare/head branch is backport-852-to-1.0.latest.