Fix data vector size in gtest

test/gtest_factor_diff_drive.cpp

@@ -626,7 +626,7 @@ TEST(FactorDiffDrive, preintegrate_and_solve_sensor_intrinsics)
 
     // right turn 90 deg in N steps --> ends up in (1.5, -1.5, -pi/2)
     int N = 6;
-    Vector3d data;
+    Vector2d data;
     Matrix2d data_cov; data_cov.setIdentity();
 
     data(0) = 0.50*intr->ticks_per_wheel_revolution / N;