Convert entity property to entry property type.

[maliming]

Fix #4917

[hikalkan]

But we also want to set null if entity.GetProperty(property.Name) returns null. Because we already checked entity.HasProperty(property.Name) before. So, if entity.GetProperty(property.Name) returns null that means it is intentionally set to null. It doesn't mean the property is missing. So, skipping if entityProperty == null makes a breaking change and breaks the current behavour. This would be better:

if (entityProperty == null)
                {
entry.Property(property.Name).CurrentValue = null;
                    continue;
}

[maliming]

I updated the code and unit test.