Updating to MSAL.NET 4.21.0 (#171)

Author: jmprieur

1. Desktop app calls Web API/TodoListClient/TodoListClient.csproj

@@ -109,7 +109,7 @@
   </ItemGroup>
   <ItemGroup>
     <PackageReference Include="Microsoft.Identity.Client">
-      <Version>4.19.0</Version>
+      <Version>4.21.0</Version>
     </PackageReference>
     <PackageReference Include="Newtonsoft.Json">
       <Version>11.0.2</Version>

2. Web API now calls Microsoft Graph/TodoListClient/TodoListClient.csproj

@@ -109,7 +109,7 @@
   </ItemGroup>
   <ItemGroup>
     <PackageReference Include="Microsoft.Identity.Client">
-      <Version>4.19.0</Version>
+      <Version>4.21.0</Version>
     </PackageReference>
     <PackageReference Include="Newtonsoft.Json">
       <Version>11.0.2</Version>

4.-Console-app-calls-web-API-with-PoP/TodoListClient/TodoListClient.csproj

@@ -94,7 +94,7 @@
   </ItemGroup>
   <ItemGroup>
     <PackageReference Include="Microsoft.Identity.Client">
-      <Version>4.19.0</Version>
+      <Version>4.21.0</Version>
     </PackageReference>
     <PackageReference Include="Newtonsoft.Json">
       <Version>11.0.2</Version>