Ignore port when using UpstreamHost option (#1505)

* Ignore port when using UpstreamHost option

* Update src/Ocelot/DownstreamRouteFinder/Middleware/DownstreamRouteFinderMiddleware.cs

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Co-authored-by: Raman Maksimchuk <[email protected]>

Author: grssmnn

src/Ocelot/DownstreamRouteFinder/Middleware/DownstreamRouteFinderMiddleware.cs

@@ -27,7 +27,10 @@ public async Task Invoke(HttpContext httpContext)
 
             var upstreamQueryString = httpContext.Request.QueryString.ToString();
 
-            var upstreamHost = httpContext.Request.Headers["Host"];
+            var hostHeader = httpContext.Request.Headers["Host"].ToString();
+            var upstreamHost = hostHeader.Contains(':')
+                ? hostHeader.Split(':')[0]
+                : hostHeader;
 
             Logger.LogDebug($"Upstream url path is {upstreamUrlPath}");