Use `cisagov/setup-env-github-action` to provide the Python and Go versions to use

[mcdonnnj]

🗣 Description

This pull request updates the build workflow to use the versions of Python and Go tracked in cisagov/setup-env-github-actions added with https://github.com/cisagov/setup-env-github-action/pull/70.

[!NOTE] This pull request should replace #154 if it is approved.

💭 Motivation and context

This change will make it easier to update to new versions of Python and Go when they release. It will also make updates significantly easier and more consistent in downstream repositories that have these values hard-coded in multiple jobs (once this change is propagated).

🧪 Testing

Automated tests pass.

✅ Pre-approval checklist

• [x] This PR has an informative and human-readable title.
• [x] Changes are limited to a single goal - eschew scope creep!
• [x] All relevant type-of-change labels have been added.
• [x] I have read the CONTRIBUTING document.
• [x] These code changes follow cisagov code standards.
• [x] All new and existing tests pass.

✅ Pre-merge checklist

• [x] Revert dependencies to default branches.

[!NOTE] I plan on rebasing to remove the commit if cisagov/setup-env-github-action#70 is approved and merged.