Remove/Replace xenavalkyrie Support

[Emantor]

Upstream notes that the xenavalkyrie module is end of life . It is replaced by the Xena Open Automation Python API. So we either remove the support or somebody with the hardware implements support for the new API.

[jluebbe]

@krevsbech Are you still using the Xena support?

[Bastian-Krause]

The latest version of xenavalkyrie==3.0.1 pins pypacker==4.9. This results in errors when used with setuptools==67.0.0:

Collecting pypacker==4.9
  Using cached pypacker-4.9.tar.gz (612 kB)
  Preparing metadata (setup.py) ... error
  error: subprocess-exited-with-error
  
  × python setup.py egg_info did not run successfully.
  │ exit code: 1
  ╰─> [1 lines of output]
      error in pypacker setup command: 'python_requires' must be a string containing valid version specifiers; Invalid specifier: '>=3.3.*'
      [end of output]

setuptools' changelog states that "users will experience a more strict parsing of requirements. Specifications that don't comply with PEP 440 and PEP 508 will result in build errors". pypacker==4.9 does not contain the necessary fix.

[jluebbe]

As a first step, we should probably remove the Xena dependencies from the dev extra to fix installation.