[Backport next] CI: Update to use Github App (#516) #768

Job	Run time
generate_target_matrix	3s
build_firmware (armsr-armv7)	1h 17m 19s
build_firmware (armsr-armv8)	1h 26m 53s
build_firmware (ath79-generic)	1h 20m 56s
build_firmware (ath79-mikrotik)	1h 16m 0s
build_firmware (ath79-nand)	1h 17m 25s
build_firmware (bcm27xx-bcm2708)	1h 9m 33s
build_firmware (bcm27xx-bcm2709)	1h 17m 59s
build_firmware (bcm27xx-bcm2710)	1h 22m 48s
build_firmware (bcm27xx-bcm2711)	1h 25m 49s
build_firmware (ipq40xx-generic)	1h 18m 49s
build_firmware (ipq40xx-mikrotik)	1h 16m 59s
build_firmware (ipq806x-generic)	1h 16m 7s
build_firmware (kirkwood-generic)	1h 17m 35s
build_firmware (lantiq-xrx200)	1h 21m 53s
build_firmware (lantiq-xway)	1h 16m 14s
build_firmware (mediatek-filogic)	1h 27m 29s
build_firmware (mediatek-mt7622)	1h 25m 12s
build_firmware (mpc85xx-p1010)	1h 17m 40s
build_firmware (mpc85xx-p1020)	1h 14m 49s
build_firmware (mvebu-cortexa9)	1h 17m 6s
build_firmware (ramips-mt7620)	1h 16m 5s
build_firmware (ramips-mt7621)	1h 20m 50s
build_firmware (ramips-mt76x8)	1h 16m 31s
build_firmware (realtek-rtl838x)	1h 9m 15s
build_firmware (rockchip-armv8)	1h 25m 20s
build_firmware (sunxi-cortexa7)	1h 10m 56s
build_firmware (x86-64)	1h 31m 54s
build_firmware (x86-generic)	1h 27m 31s
build_firmware (x86-geode)	1h 24m 11s
build_firmware (x86-legacy)	1h 24m 27s
create_release	0s
	1d 15h 51m 38s

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