Bump to 0.3.1

[mhogan-nwra]

Topic

Bump envector to version 0.3.1

Steps

1. Include an example for use

No changes to the API were introduced. Static typing usage was expanded or fixed.

2. Add a note to CHANGELOG.rst about the changes

Done

3. Update the author list in AUTHORS.rst if applicable

Already done.

4. Ensure that all checks passed (current checks include GitHub Actions)

Ran pytest locally.

[mhogan-nwra]

Decision

This pull request has been declined.

Reason

All Actions failed with Python <3.11. The typing.Self is not a standard library feature prior to 3.11.

Resolution

Remove all instances of typing.Self. Next time run nox to avoid this problem.