Add autotest for Solo mount #38301

Job	Run time
build (base)	5m 16s
build (clang)	5m 26s
build-gcc-heli	5m 6s
autotest (sitltest-copter-tests1a)	8m 15s
autotest (sitltest-copter-tests1b)	10m 16s
autotest (sitltest-copter-tests1c)	11m 59s
autotest (sitltest-copter-tests1d)	9m 9s
autotest (sitltest-copter-tests1e)	9m 27s
autotest (sitltest-copter-tests2a)	9m 56s
autotest (sitltest-copter-tests2b)	29m 25s
autotest-heli (sitltest-heli)	10m 32s
	1h 54m 47s

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