try to fix submodule

firmware/lib/Arduino-FOC-drivers/src/motors/HybridStepperMotor/README.md

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+# Three Phase / Hybrid Stepper Motor Class
+
+By tying two phases together, you can use a standard bipolar stepper motor with three-phase drivers!
+Of course, it requires some different math for commutation. Another limitation is that with SinePWM the motor voltage is limited to 50% of the supply voltage. Using some tricks in SpaceVectorPWM, this max bias can be increased to about 70%.
+
+## Warning
+
+This code has not been tested much! 
+It has killed one B-G431B-ESC1 board before. 
+However, it has been succesfully used on a few different hardware platforms, so it does work.
+BEMF may be the danger here, so take caution with fast decelerations.
+Keep in mind that potentially twice the current can be sunk in the shorted phase as the two other legs.
+
+## Hardware setup
+
+Tie two of the phases of the motor together. This is phase "C". The other two phases are A & B. Phase C must go last in the driver constructor. 
+
+
+## Software setup
+
+Usage is quite simple: 
+
+```c++
+#include "Arduino.h"
+#include "SimpleFOC.h"
+#include "SimpleFOCDrivers.h"
+#include "motors/HybridStepperMotor/HybridStepperMotor.h"
+
+HybridStepperMotor motor = HybridStepperMotor(pole_pairs, phase_resistance, kv, winding_inductance);
+BLDCDriver3PWM driver = BLDCDriver3PWM(phase_A, phase_B, phase_C, enable);
+
+void setup() {
+    driver.init();
+    motor.linkDriver(&driver);
+
+    motor.foc_modulation = FOCModulationType::SpaceVectorPWM; //or SinePWM
+    motor.init();
+    motor.initFOC();
+}
+
+void loop(){
+    motor.loopFOC();
+    motor.move();
+}
+```