Include thirdparty libraries with angle brackets (#5578)

wpimath/src/test/native/cpp/EigenTest.cpp

@@ -2,9 +2,10 @@
 // Open Source Software; you can modify and/or share it under the terms of
 // the WPILib BSD license file in the root directory of this project.
 
-#include "Eigen/LU"
+#include <Eigen/LU>
+#include <gtest/gtest.h>
+
 #include "frc/EigenCore.h"
-#include "gtest/gtest.h"
 
 TEST(EigenTest, Multiplication) {
   frc::Matrixd<2, 2> m1{{2, 1}, {0, 1}};