Updated ARG keyword documentation in PythonFunction for pycv #3018

Job	Run time
codecheck / codecheck	44m 26s
docker / docker (fedora39)	20m 40s
conda / conda (ubuntu-20.04)	11m 5s
docker / docker (rocky8)	23m 7s
linux / linux (-doc-mpi-)	42m 23s
conda / conda (macos-12)	26m 20s
linux / linux (-mpi-)	50m 12s
conda / conda (macos-14)	6m 52s
mac / macports (macos-12)	18m 1s
linux / linux (-coverage-mpi-)	1h 2m 35s
mac / macports (macos-14)	8m 13s
linux / linux (-debug-)	30m 22s
mac / macsimple (macos-12)	12m 1s
mac / macports (+allmodules, macos-12)	24m 6s
mac / macsimple (macos-14)	5m 21s
linux / linux (-debug-mpi-)	41m 21s
linux / linux (-intel-)	46m 49s
linux / linux (-pycv-mpi-)	18m 4s
	8h 11m 58s

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