Update to poetry 2.1.2

Author: ArBridgeman

doc/changes/unreleased.md

@@ -8,4 +8,5 @@
 * [#372](https://github.com/exasol/python-toolbox/issues/372): Added conversion from pip-audit JSON to expected GitHub Issue format
 
 ## ⚒️ Refactorings
-* [#388](https://github.com/exasol/python-toolbox/issues/388): Switch GitHub workflows to use pinned OS version
+* [#388](https://github.com/exasol/python-toolbox/issues/388): Switch GitHub workflows to use pinned OS version
+* [#376](https://github.com/exasol/python-toolbox/issues/376): Update to poetry 2.1.2