added missing default value for min_pitch

Author: gbarter

rosco/toolbox/inputs/toolbox_schema.yaml

@@ -318,6 +318,7 @@ properties:
             min_pitch:           
                 description: Minimum pitch angle [rad]
                 type: number
+                default: 0.0
                 unit: rad
             vs_minspd:           
                 description: Minimum rotor speed [rad/s], {default = 0 rad/s}