Set process encoding

Author: TanayParikh

src/Tests/dotnet-watch.Tests/Utilities/AwaitableProcess.cs

@@ -51,6 +51,8 @@ public void Start()
             var processStartInfo = _spec.GetProcessStartInfo();
             processStartInfo.RedirectStandardOutput = true;
             processStartInfo.RedirectStandardError = true;
+            processStartInfo.StandardOutputEncoding = Encoding.UTF8;
+            processStartInfo.StandardErrorEncoding = Encoding.UTF8;
             processStartInfo.Environment["DOTNET_SKIP_FIRST_TIME_EXPERIENCE"] = "true";
 
             _process = new Process