Version 1.9.4

This is a micro release with a small number of bug fixes and compatibility fixes with HoloViews 1.14.8 and support for Python 3.10.

Bug fixes:

• Fix handling of 3-channel RGB element (#558)
• Add support for pandas Float64Array (#559)

Compatibility:

• Compatibility with HoloViews 1.14.8 (#556)
• Compatibility with Python 3.10 by replacing LooseVersion with packaging.Version (#555)