Add ping supervisor proxy #205

Job	Run time
Build landingpage (generic-x86-64)	25s
Build landingpage (intel-nuc)	25s
Build landingpage (khadas-vim3)	59s
Build landingpage (odroid-c2)	59s
Build landingpage (odroid-c4)	1m 1s
Build landingpage (odroid-m1)	1m 11s
Build landingpage (odroid-n2)	1m 2s
Build landingpage (odroid-xu)	1m 7s
Build landingpage (qemuarm)	1m 23s
Build landingpage (qemuarm-64)	1m 0s
Build landingpage (qemux86)	32s
Build landingpage (qemux86-64)	24s
Build landingpage (raspberrypi)	1m 23s
Build landingpage (raspberrypi2)	59s
Build landingpage (raspberrypi3)	58s
Build landingpage (raspberrypi3-64)	1m 8s
Build landingpage (raspberrypi4)	1m 1s
Build landingpage (raspberrypi4-64)	1m 11s
Build landingpage (raspberrypi5-64)	1m 0s
Build landingpage (tinker)	59s
Build landingpage (yellow)	1m 8s
Build landingpage (green)	1m 1s
	21m 16s

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