Add support for Python 3.12

[falkoschindler]

This PR adds support for Python 3.12.

Most significant changes are:

• Update the Python version limit from 3.11 to 3.12
• Introduce an async Automation.run() method which can be passed to NiceGUI's background_tasks.create() without violating the iscoroutine assertion.
• Cleanup and update dependencies
  Especially uvloop needs at least 0.18 for Python 3.12.
  But deptry unveiled several unused dependencies that could be removed.
  There are probably more dependency definitions that could be relaxed to allow newer versions.