The `actions/checkout@v2` GitHub action uses Node 12, which is
deprecated and scheduled for end-of-life in Summer 2023; see
https://github.blog/changelog/2022-09-22-github-actions-all-actions-will-begin-running-on-node16-instead-of-node12/
for details.

This commit updates the CI workflows to use `actions/checkout@v3`
instead, which upgrades that action to use Node 16.

Signed-off-by: Geoffrey M Oxberry <goxberry@gmail.com>

The `actions/setup-python@v1` action is another deprecated Node 12
action slated for removal by Summer 2023. This commit updates that
action to `actions/setup-python@v4` to resolve the deprecation
warnings seen in CI output.

Signed-off-by: Geoffrey M Oxberry <goxberry@gmail.com>

The `pre-commit/action@v2.0.0` action is the last of the remaining
Node 12 actions used by the project's CI wokflow. This commit upgrades
that action to `pre-commit/action@v3.0.0`, which uses Node 16 and is
not subject to deprecation.

Signed-off-by: Geoffrey M Oxberry <goxberry@gmail.com>