Add coverage badge.

Refactor chrome config.

Author: rosolko

README.md

@@ -1,5 +1,6 @@
 [![Build status](https://ci.appveyor.com/api/projects/status/kjpqb5twmpxw6lpl?svg=true)](https://ci.appveyor.com/project/rosolko/webdrivermanager-net)
 [![Quality Gate](https://sonarcloud.io/api/project_badges/measure?project=webdrivermanager.net&metric=alert_status)](https://sonarcloud.io/dashboard?id=webdrivermanager.net)
+[![Coverage](https://sonarcloud.io/api/project_badges/measure?project=webdrivermanager.net&metric=coverage)](https://sonarcloud.io/dashboard?id=webdrivermanager.net)
 [![NuGet](https://img.shields.io/nuget/v/WebDriverManager.svg)](https://www.nuget.org/packages/WebDriverManager)
 
 # WebDriverManager.Net

WebDriverManager/DriverConfigs/Impl/ChromeConfig.cs

@@ -28,12 +28,13 @@ public virtual string GetBinaryName()
 
         public virtual string GetLatestVersion()
         {
-            var webRequest = WebRequest.Create("https://chromedriver.storage.googleapis.com/LATEST_RELEASE");
+            var uri = new Uri("https://chromedriver.storage.googleapis.com/LATEST_RELEASE");
+            var webRequest = WebRequest.Create(uri);
             using (var response = webRequest.GetResponse())
             {
                 using (var content = response.GetResponseStream())
                 {
-                    if (content == null) throw new Exception("Unable to get latest chrome version");
+                    if (content == null) throw new ArgumentNullException($"Can't get content from URL: {uri}");
                     using (var reader = new StreamReader(content))
                     {
                         var version = reader.ReadToEnd().Trim();