Support falling back to ConnectionId when RawConnectionId is 0 on HTTP.sys (#40760)

Author: Tratcher

src/Servers/HttpSys/src/RequestProcessing/Request.cs

@@ -120,7 +120,7 @@ internal Request(RequestContext requestContext)
         internal ulong RawConnectionId { get; }
 
         // No ulongs in public APIs...
-        public long ConnectionId => (long)RawConnectionId;
+        public long ConnectionId => RawConnectionId != 0 ? (long)RawConnectionId : (long)UConnectionId;
 
         internal ulong RequestId { get; }