change logic to use ones_like instead of full_like

aerosandbox/optimization/opti.py

@@ -1154,7 +1154,7 @@ def constrain_derivative(self,
         try:
             derivative[0]
         except (TypeError, IndexError):
-            derivative = np.full_like(with_respect_to, fill_value=derivative)
+            derivative = np.ones_like(with_respect_to) * derivative
 
         # TODO scale constraints by variable scale?
         # TODO make