Python: Added Snoop as a development dependency (microsoft#2457)

### Motivation and Context

Add snoop as a dev dependency for easier debugging of tests.

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### Description

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### Contribution Checklist

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- [x] The code builds clean without any errors or warnings
- [x] The PR follows the [SK Contribution
Guidelines](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md)
and the [pre-submission formatting
script](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md#development-scripts)
raises no violations
- [x] All unit tests pass, and I have added new tests where possible
- [x] I didn't break anyone 😄

Co-authored-by: Abby Harrison <[email protected]>

Author: 2 people