graphics/py-webcolors: update to 24.8.0

Update to the latest version to fix dependant ports:

ERROR Missing dependencies:
        jupyterlab~=4.0
        jupyterlab-server<3,>=2.27.1 -> jupyter-server<3,>=1.21 -> jupyter-events>=0.9.0 -> jsonschema[format-nongpl]>=4.18.0 -> webcolors>=24.6.0

Approved by:	portmgr (blanket)