Only run posthog if running in production

[KIRA009]

What kind of change does this PR introduce? This PR changes the posthog init, such that it only runs on production mode, i.e. when run from within the executable, and a couple other small fixes

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• [x] My code follows the style guidelines of OpenAdapt
• [x] I have performed a self-review of my code
• [ ] If applicable, I have added tests to prove my fix is functional/effective
• [x] I have linted my code locally prior to submission
• [ ] I have commented my code, particularly in hard-to-understand areas
• [ ] I have made corresponding changes to the documentation (e.g. README.md, requirements.txt)
• [x] New and existing unit tests pass locally with my changes

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