[dotnet] Fix race condition for .net framework when internal tracing enabled (#16091)

This exception might be happened in .NET Framework only. On .NET Core it works smoothly.

System.ArgumentException: An item with the same key has already been added.
   at System.ThrowHelper.ThrowArgumentException(ExceptionResource resource)
   at System.Collections.Generic.Dictionary`2.Insert(TKey key, TValue value, Boolean add)
   at System.Net.Http.Headers.HttpHeaders.AddHeaderToStore(String name, HeaderStoreItemInfo info)
   at System.Net.Http.Headers.HttpHeaders.CreateAndAddHeaderToStore(String name)
   at System.Net.Http.Headers.HttpHeaders.GetOrCreateHeaderInfo(String name, Boolean parseRawValues)
   at System.Net.Http.Headers.HttpHeaders.SetParsedValue(String name, Object value)
   at System.Net.Http.Headers.HttpContentHeaders.get_ContentLength()
   at System.Net.Http.HttpClientHandler.PrepareAndStartContentUpload(RequestState state)

Author: nvborisenko

dotnet/src/webdriver/Remote/HttpCommandExecutor.cs

@@ -440,8 +440,6 @@ public DiagnosticsHttpHandler(HttpMessageHandler messageHandler, ILogger logger)
         /// <returns>The http response message content.</returns>
         protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
         {
-            var responseTask = base.SendAsync(request, cancellationToken);
-
             StringBuilder requestLogMessageBuilder = new();
             requestLogMessageBuilder.AppendFormat(">> {0} RequestUri: {1}, Content: {2}, Headers: {3}",
                 request.Method,
@@ -451,20 +449,30 @@ protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage
 
             if (request.Content != null)
             {
+#if NET8_0_OR_GREATER
+                var requestContent = await request.Content.ReadAsStringAsync(cancellationToken).ConfigureAwait(false);
+#else
                 var requestContent = await request.Content.ReadAsStringAsync().ConfigureAwait(false);
+#endif
                 requestLogMessageBuilder.AppendFormat("{0}{1}", Environment.NewLine, requestContent);
             }
 
             _logger.Trace(requestLogMessageBuilder.ToString());
 
-            var response = await responseTask.ConfigureAwait(false);
+            var response = await base.SendAsync(request, cancellationToken).ConfigureAwait(false);
 
             StringBuilder responseLogMessageBuilder = new();
+
             responseLogMessageBuilder.AppendFormat("<< StatusCode: {0}, ReasonPhrase: {1}, Content: {2}, Headers: {3}", (int)response.StatusCode, response.ReasonPhrase, response.Content, response.Headers?.Count());
 
             if (!response.IsSuccessStatusCode && response.Content != null)
             {
+#if NET8_0_OR_GREATER
+                var responseContent = await response.Content.ReadAsStringAsync(cancellationToken).ConfigureAwait(false);
+#else
                 var responseContent = await response.Content.ReadAsStringAsync().ConfigureAwait(false);
+#endif
+
                 responseLogMessageBuilder.AppendFormat("{0}{1}", Environment.NewLine, responseContent);
             }