Auto merge of #22094 - asajeffrey:magicleap-shutdown, r=paulrouget

Shut down Servo when the ML app quits

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Shut down servo when shutting down the magic leap app.

---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes do not require tests because we don't test ML

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support/magicleap/Servo2D/code/src/Servo2D.cpp

@@ -59,8 +59,6 @@ Servo2D::Servo2D() {
 // Destroy a Servo 2D instance
 Servo2D::~Servo2D() {
   ML_LOG(Debug, "Servo2D Destructor.");
-  discard_servo(servo_);
-  servo_ = nullptr;
 }
 
 // The prism dimensions
@@ -168,6 +166,8 @@ int Servo2D::init() {
 
 int Servo2D::deInit() {
   ML_LOG(Debug, "Servo2D Deinitializing.");
+  discard_servo(servo_);
+  servo_ = nullptr;
   return 0;
 }