Document how to start Synapse with Poetry (#14892)

* Add Start Synapse with Poetry

* Create 14892.doc

* Apply suggestions from code review

Co-authored-by: Sean Quah <8349537+squahtx@users.noreply.github.com>

* Update docs/workers.md

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Co-authored-by: David Robertson <david.m.robertson1@gmail.com>
Co-authored-by: Sean Quah <8349537+squahtx@users.noreply.github.com>