Updating C# Playground/Test certs to fix appveyor build (#2175)

Author: jonthysell

ReactWindows/Playground/Playground.csproj

@@ -18,7 +18,7 @@
     <ProjectTypeGuids>{A5A43C5B-DE2A-4C0C-9213-0A381AF9435A};{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}</ProjectTypeGuids>
     <PackageCertificateKeyFile>Playground_TemporaryKey.pfx</PackageCertificateKeyFile>
     <DependencyConfiguration>Debug</DependencyConfiguration>
-    <PackageCertificateThumbprint>50F337BA80C1751C2DE37B18FCFCA55368EC6A3C</PackageCertificateThumbprint>
+    <PackageCertificateThumbprint>218F5339D3F55118F3F99818E3D252192FEA960C</PackageCertificateThumbprint>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)' == 'Debug' or '$(Configuration)' == 'DebugBundle'">
     <DependencyConfiguration>Debug</DependencyConfiguration>

ReactWindows/Playground/Playground_TemporaryKey.pfx

@@ -19,7 +19,7 @@
     <PackageCertificateKeyFile>ReactNative.Tests_TemporaryKey.pfx</PackageCertificateKeyFile>
     <UnitTestPlatformVersion Condition="'$(UnitTestPlatformVersion)' == ''">14.0</UnitTestPlatformVersion>
     <DependencyConfiguration>Debug</DependencyConfiguration>
-    <PackageCertificateThumbprint>F0FB82837F45EE9E0EFC3B38576F3C1523EAC45A</PackageCertificateThumbprint>
+    <PackageCertificateThumbprint>F983A63678123AECBF104DEBC8E7B2B3080F1C01</PackageCertificateThumbprint>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)' == 'Debug' or '$(Configuration)' == 'DebugBundle'">
     <DependencyConfiguration>Debug</DependencyConfiguration>