Use latest release of pshtt

[jsf9k]

🗣 Description

This pull request updates the code to:

• Use the Python 3.7 AWS Lambda runtime
• Install/upgrade wheel at the same time as pip and setuptools
• Use the latest release of cisagov/pshtt

💭 Motivation and context

• The Python 3.6 runtime is no longer supported by AWS Lambda.
• The wheel package is preferred to setuptools for many packages.
• The latest release of cisagov/pshtt fixes a bug.

🧪 Testing

I successfully used these changes to deploy an updated pshtt Lambda. The TravisCI builds are failing because we no longer use TravisCI.

✅ Pre-approval checklist

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

✅ Pre-merge checklist

• Finalize version.

✅ Post-merge checklist

• Create a release.

[mcdonnnj]

Seems reasonable enough. I had one question and then I'm not sure if you feel like dealing with it right now but it'd be nice if long command line options were used throughout the Dockerfiles/build scripts.

[jsf9k]

it'd be nice if long command line options were used throughout the Dockerfiles/build scripts

Given that the long-term plan is to move this jazz to the new skeleton you created, I don't want to invest that effort right now. You can create an issue if you want to.

[dav3r]

👍 👍 👍