Update supported-package-managers.md

Added a section on poetry to clarify that PEP 621 projects aren't supported.

Author: Sharra-writes

data/reusables/dependabot/supported-package-managers.md

@@ -144,6 +144,10 @@ In addition to supporting updates to `requirements.txt` files, {% data variables
 pnpm is supported for {% data variables.product.prodname_dependabot_version_updates %} (on v7, v8, and v9) and {% data variables.product.prodname_dependabot_security_updates %} (on v7 and v8 only).
 {% endif %}
 
+####poetry
+
+The [PEP 621](https://python-poetry.org/blog/announcing-poetry-2.0.0/#supporting-the-project-section-in-pyprojecttoml-pep-621) `project` section isn't currently supported for `poetry`
+
 #### pub
 
 {% data variables.product.prodname_dependabot %} won't perform an update for `pub` when the version that it tries to update to is ignored, even if an earlier version is available.