Updating devlopment and test dependencies: molecule, molecule-vagrant, testinfra, pytest

[kushaldas]

Description

We are very old versions of a few development/test dependencies. This means any future updating will require more work (as many functions/commands, syntaxt of YAML files for molecule are already deprecated and dropped from upstream). It will also bring latest changes in molecule + vagrant for staging/testinfra work.

Differences in version

• molecule: we are using 2.22 and upstream is at 3.0.8, this also requires YAML file changes for molecule syntax.
• molecule-vagrant: Can only be along with molecule package
• testinfra: we are using 3.2.0 and upstream is at 5.3.1, even the testinfra command is deprecated and dropped from code.
• pytest: We are using 3.2.0 and upstream is at 6.0.2. Code will require updates as many currently used functions are already dropped