Try better variable

Author: rmarinho

eng/pipelines/handlers.yml

@@ -188,7 +188,7 @@ stages:
           displayName: 'Install .NET'
           retryCountOnTaskFailure: 3
           env:
-            DOTNET_TOKEN: $(dotnetbuilds-internal-container-read-token)
+            DOTNET_TOKEN: $(dotnetbuilds-internal-container-read-token-base64)
             PRIVATE_BUILD: $(PrivateBuild)
         - pwsh: ./build.ps1 --target=dotnet-build --configuration="${{ BuildConfiguration }}" --verbosity=diagnostic
           displayName: 'Build .NET Maui'
@@ -302,7 +302,7 @@ stages:
         displayName: 'Install .NET (Local Workloads)'
         retryCountOnTaskFailure: 3
         env:
-          DOTNET_TOKEN: $(dotnetbuilds-internal-container-read-token)
+          DOTNET_TOKEN: $(dotnetbuilds-internal-container-read-token-base64)
           PRIVATE_BUILD: $(PrivateBuild)
       - pwsh: ./build.ps1 --target=dotnet-integration-build --verbosity=diagnostic
         displayName: Build Microsoft.Maui.IntegrationTests