fix(test): pin tox versions and update unit/int file specifiers

[c-ryan-k]

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This project has adopted the Microsoft Open Source Code of Conduct. For more information see the Code of Conduct FAQ or contact opencode@microsoft.com with any additional questions or comments.

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This checklist is used to make sure that common guidelines for a pull request are followed.

General Guidelines

Intent for Production

• It is expected that pull requests made to default or core branches such as dev or main are of production grade. Corollary to this, any merged contributions to these branches may be deployed in a public release at any given time. By checking this box, you agree and commit to the expected production quality of code.

Basic expectations

• If introducing new functionality or modified behavior, are they backed by unit and/or integration tests?
• In the same context as above are command names and their parameter definitions accurate? Do help docs have sufficient content?
• Have all the relevant unit and integration tests pass? i.e. pytest <project root> -vv. Please provide evidence in the form of a screenshot showing a succesful run of tests locally OR a link to a test pipeline that has been run against the change-set.
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