board_types.txt: reserve board ID for MountainEagle H743 #38432

Job	Run time
build (stm32f7, chibios, 10)	14m 48s
build (stm32h7, chibios, 10)	12m 44s
build (fmuv2-plane, chibios, 10)	5m 47s
build (periph-build, chibios, 10)	14m 27s
build (iofirmware, chibios, 10)	2m 29s
build (CubeOrange-bootloader, chibios, 10)	1m 7s
build (fmuv3-bootloader, chibios, 10)	1m 22s
build (revo-bootloader, chibios, 10)	1m 14s
build (stm32h7-debug, chibios, 10)	7m 3s
build (fmuv3, chibios, 10)	13m 34s
build (revo-mini, chibios, 10)	10m 41s
build (MatekF405-Wing, chibios, 10)	11m 11s
build (CubeOrange-ODID, chibios, 10)	8m 50s
build (CubeRedPrimary-bootloader, chibios, 10)	1m 10s
build (configure-all, chibios, 10)	9m 53s
build (build-options-defaults-test, chibios, 10)	27m 30s
build (signing, chibios, 10)	9m 56s
build (CubeOrange-PPP, chibios, 10)	7m 18s
build (SOHW, chibios, 10)	13m 4s
build (Pixhawk6X-PPPGW, chibios, 10)	3m 17s
	2h 57m 25s

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