[wpiutil] Deprecate wpi::math constants in favor of wpi::numbers (#3383)

The constants were moved from std::math to std::numbers before
ratification in C++20.

wpilibcExamples/src/main/cpp/examples/MecanumBot/include/Drivetrain.h

@@ -13,7 +13,7 @@
 #include <frc/kinematics/MecanumDriveOdometry.h>
 #include <frc/kinematics/MecanumDriveWheelSpeeds.h>
 #include <frc/motorcontrol/PWMSparkMax.h>
-#include <wpi/math>
+#include <wpi/numbers>
 
 /**
  * Represents a mecanum drive style drivetrain.
@@ -32,7 +32,7 @@ class Drivetrain {
   static constexpr units::meters_per_second_t kMaxSpeed =
       3.0_mps;  // 3 meters per second
   static constexpr units::radians_per_second_t kMaxAngularSpeed{
-      wpi::math::pi};  // 1/2 rotation per second
+      wpi::numbers::pi};  // 1/2 rotation per second
 
  private:
   frc::PWMSparkMax m_frontLeftMotor{1};