[dotnet] Improve bidi exception when it is not enabled

Author: nvborisenko

dotnet/src/webdriver/BiDi/WebDriver.Extensions.cs

@@ -30,7 +30,7 @@ public static async Task<BiDi> AsBiDiAsync(this IWebDriver webDriver)
     {
         var webSocketUrl = ((IHasCapabilities)webDriver).Capabilities.GetCapability("webSocketUrl");
 
-        if (webSocketUrl is null) throw new System.Exception("The driver is not compatible with bidirectional protocol or it is not enabled in driver options.");
+        if (webSocketUrl is null) throw new BiDiException("The driver is not compatible with bidirectional protocol or \"webSocketUrl\" not enabled in driver options.");
 
         var bidi = await BiDi.ConnectAsync(webSocketUrl.ToString()!).ConfigureAwait(false);