fix(mypy): catch Python 3.8-specific errors

[DavidVujic]

Description

Configure MyPy to find things that won't work in Python 3.8.

Motivation and Context

To be notified early about the difference between the Python versions, such as missing typing.Dict.

How Has This Been Tested?

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

• I have read the code of conduct.
• I have read the contributing guide.
• I have updated the documentation accordingly (if applicable).

[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!   

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0 Vulnerabilities
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