Use defaulted comparison operators in C++ (#4723)

Comparison operators which compared against every class member variable
now use C++20's default comparison operators.

Also remove operator!= that in C++20 is now auto-generated from operator==.

wpimath/src/main/native/cpp/geometry/Quaternion.cpp

@@ -33,10 +33,6 @@ bool Quaternion::operator==(const Quaternion& other) const {
   return std::abs(m_r * other.m_r + m_v.dot(other.m_v)) > 1.0 - 1E-9;
 }
 
-bool Quaternion::operator!=(const Quaternion& other) const {
-  return !operator==(other);
-}
-
 Quaternion Quaternion::Inverse() const {
   return Quaternion{m_r, -m_v(0), -m_v(1), -m_v(2)};
 }