Fixed "Data is null" exception when NumberOfShortInspectionsSinceLast…

…FullInspection is null in the database but it is set as not null in the EF entity (#672)

Dfe.Academies.Domain/Establishment/FurtherEducationEstablishment.cs

@@ -11,7 +11,7 @@ public class FurtherEducationEstablishment
     public string? Region { get; set; }
     public string? OfstedRegion { get; set; }
     public string? DateOfLatestShortInspection { get; set; }
-    public int NumberOfShortInspectionsSinceLastFullInspection { get; set; }
+    public int? NumberOfShortInspectionsSinceLastFullInspection { get; set; }
     public string? InspectionNumber { get; set; }
     public string? InspectionType { get; set; }
     public string? FirstDayOfInspection { get; set; }