Update dependencies from https://github.com/dotnet/arcade build 20190819.12

- Microsoft.DotNet.Arcade.Sdk - 1.0.0-beta.19419.12

eng/Version.Details.xml

@@ -3,9 +3,9 @@
   <ProductDependencies>
   </ProductDependencies>
   <ToolsetDependencies>
-    <Dependency Name="Microsoft.DotNet.Arcade.Sdk" Version="1.0.0-beta.19416.16">
+    <Dependency Name="Microsoft.DotNet.Arcade.Sdk" Version="1.0.0-beta.19419.12">
       <Uri>https://github.com/dotnet/arcade</Uri>
-      <Sha>0e36c2410b72166a1b9a67142e652225e22feada</Sha>
+      <Sha>10b2260aeed5f07582bf8d8dcd4221a447b171c5</Sha>
     </Dependency>
   </ToolsetDependencies>
 </Dependencies>

global.json

@@ -10,7 +10,7 @@
     }
   },
   "msbuild-sdks": {
-    "Microsoft.DotNet.Arcade.Sdk": "1.0.0-beta.19416.16",
+    "Microsoft.DotNet.Arcade.Sdk": "1.0.0-beta.19419.12",
     "Microsoft.DotNet.Helix.Sdk": "2.0.0-beta.19069.2"
   }
 }