Don't use py3.5+ only subprocess.run in python invoke local

[dschep]

What did you implement:

Fixes #5499

invoke local was changed in #5355 to check for a tty by calling the tty executable, but it was implemented with subprocess.run which was added in Python 3.5 so it doesn't work with Python 2.7 projects

How did you implement it:

Switched to the older subprocess.check_call

How can we verify it:

npm i -g serverless/serverless#fix-py27-invoke-local
sls create -t aws-python
sls invoke local -f hello

Todos:

• Write tests
• Write documentation
• Fix linting errors
• Make sure code coverage hasn't dropped
• Provide verification config / commands / resources
• Enable "Allow edits from maintainers" for this PR
• Update the messages below

Is this ready for review?: YES
Is it a breaking change?: NO

[dschep]

@filanthropic mind testing this in the project you ran into #5499? Install as indicated in the PR description ☝️

[alexdebrie]

LGTM. Tested sls invoke local with 1.33.1 and I got the error. Ran with this branch, and sls invoke local worked successfully.