add artifacthub metadata files #152

Job	Run time
generate-matrix	4s
chart-release (open5gs-mme)	12s
chart-release (open5gs-nrf)	12s
chart-release (open5gs-nssf)	9s
chart-release (open5gs-pcf)	9s
chart-release (open5gs-pcrf)	8s
chart-release (open5gs-scp)	10s
chart-release (open5gs-sgwc)	13s
chart-release (open5gs-sgwu)	10s
chart-release (open5gs-smf)	8s
chart-release (open5gs-udm)	8s
chart-release (open5gs-udr)	11s
chart-release (open5gs-upf)	10s
chart-release (open5gs-webui)	8s
chart-release (srs-epc)	5s
chart-release (srs-ue)	6s
chart-release (srsran-4g-zmq)	8s
chart-release (srsran-4g)	9s
chart-release (srsran-5g-zmq)	11s
chart-release (srsran-5g)	11s
chart-release (ueransim-gnb)	11s
chart-release (ueransim-ues)	8s
chart-release (push-all-charts.sh)	7s
	3m 28s

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