ops-scenario 7.1.3 Put the mocked Juju environment into os.environ

What's Changed

In ops-scenario 7.1, the mocked Juju environment variables were placed directly in the _JujuContext object, rather than in os.environ as previously. We didn't announce this well, and agree that it's too significant a change to make in a minor release, so have reverted that change.

Fixes

• Expose the mocked Juju environment variables via os.environ again in #1573

Documentation

• Update logo and readme by @tmihoc in #1571
• Fill out remaining external link placeholders in #1564
• Consistently use relation as the noun and integrate as the verb in #1574

Full Changelog: 2.18.1...scenario-7.1.3