CI failures, including ImportError: cannot import name 'mock_s3' from 'moto'

[simonw]

moto made a backwards incompatible change. I dealt with this one recently here as well:

• Initial design just for JPEG and PNG textract-cli#1 (comment)

[simonw]

Looks like Moto doesn't support Python 3.7 any more:

ERROR: No matching distribution found for moto>=5.0.4; extra == "test"