VTOL mixer: Use formatting without workarounds for system test

ROMFS/px4fmu_test/mixers/vtol2_test.mix

 # E-flite Convergence Tricopter Y-Configuration Mixer
 
-# Note: 9999 is used to circumvent a mixer loading bug
-# https://github.com/PX4/Firmware/issues/5118
-
 # Motors
-R: 3y 9999 9999 9999 0
+R: 3y 10000 10000 10000 0
 
 Z:
 
@@ -13,13 +10,13 @@ Tilt mechanism servo mixer
 #RIGHT up:2000 down:1000
 M: 2
 O:      10000  10000      0 -10000  10000
-S: 1 4      0 -20000   9999 -10000  10000
+S: 1 4      0 -20000   10000 -10000  10000
 S: 0 2   4000   4000      0 -10000  10000
 
 #LEFT up:1000 down:2000
 M: 2
 O:      10000  10000      0 -10000  10000
-S: 1 4      0  20000  -9999 -10000  10000
+S: 1 4      0  20000  -10000 -10000  10000
 S: 0 2   4000   4000      0 -10000  10000
 
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