Fix use of min score increment in rejection message

src/NzbDrone.Core/DecisionEngine/Specifications/UpgradeDiskSpecification.cs

@@ -80,7 +80,7 @@ namespace NzbDrone.Core.DecisionEngine.Specifications
                     return Decision.Reject("Existing file on disk has a equal or higher custom format score: {0}", qualityProfile.CalculateCustomFormatScore(customFormats));
 
                 case UpgradeableRejectReason.MinCustomFormatScore:
-                    return Decision.Reject("Existing file differential between new release does not meet minimum Custom Format score increment: {0}", qualityProfile.MinFormatScore);
+                    return Decision.Reject("Existing file differential between new release does not meet minimum Custom Format score increment: {0}", qualityProfile.MinUpgradeFormatScore);
             }
 
             return Decision.Accept();