Fixes tests

[s1113950]

Noticed 1 of the test scenarios is failing now; will fix it here.

Working Mac setup:

Agent name: 'Hosted Agent'
Current agent version: '2.168.2'
Current image version: '20200510.1'
Downloading task: CmdLine (2.164.0)

https://dev.azure.com/dw-mitogen/Mitogen/_build/results?buildId=910&view=logs&j=03eab741-1054-5a70-27dd-24b3b6e63674&t=d1cbd9d4-af49-4555-8db3-d869f683368d

Broken Mac setup:

Agent name: 'Azure Pipelines 5'
Current agent version: '2.170.1'
Current image version: '20200607.1'
Downloading task: CmdLine (2.164.2)

https://dev.azure.com/dw-mitogen/Mitogen/_build/results?buildId=926&view=logs&j=03eab741-1054-5a70-27dd-24b3b6e63674&t=fac749a7-152c-4eb2-8af6-c5382f817336

[s1113950]

@dw not sure what's going on here 🤔 tests were all passing up until 0e47280 which just changes a README. I posted the diff of the env between the former passing commit: 921f3aa and the one I just posted. Azure DevOps updated its Mac agent and now ssh is having troubles with localhost_ansible. Gonna dig into this deeper soon so tests can be all green before going back to collections support.

[s1113950]

It's squash-merge time!