correct NOTE in orbit test case 4.2

tests/orbit_test.cpp

@@ -101,7 +101,7 @@ TEST_CASE("time of flight example 4.2", "[orbits]")
 	double r = 6378;		// body radius in km
 	system_2body sys = systemInit(gravBodyInit(mu, r), orbitInit(a, e));
 
-	// NOTE: get ToF from periapsis to true anomaly at 154.85 degrees
+	// NOTE: get ToF from true anom 230 degrees to true anom at 120 degrees
 	double theta_1 = 230 * M_PI / 180;
 	double theta_2 = 120 * M_PI / 180;