workflow updates

[sarnold]

• add missing sdist job to release workflow
• add artifact check to main workflow
• put all the artifacts in a single zip and download dir
• bump version

[sarnold]

Hold off on this for a bit while I check the workflows in my fork.

[sarnold]

Looks good here after typo fix; go ahead and delete 0.3.5 and 0.3.6 tags, then merge PR, then make a new v0.3.6 tag and push it, and the (github) release page should pick up the v0.3.4..v0.3.6 changes.

Things to remember:

• always use either a signed or annotated tag (lightweight tags don't work correctly with workflow versioning)
• my own "release" flow is to merge PR changes first, then update docs as needed, then make a commit to bump the version(s) and tag that commit (somewhat cleaner than tagging a merge commit, plus it helps me remember to actually make the changes)

[andreasvc]

Thanks!