[build] push nightly builds to dotnet8 feed (#7528)

Our pipelines should be authorized to push to the dotnet8 feed now.
Update our `.yaml` to start doing this.

Author: jonathanpeppers

build-tools/automation/azure-pipelines.yaml

@@ -58,19 +58,14 @@ variables:
   value: $[or(eq(variables['XA.RunAllTests'], true), eq(variables['IsMonoBranch'], true))]
 - name: DotNetNUnitCategories
   value: '& TestCategory != DotNetIgnore & TestCategory != HybridAOT & TestCategory != MkBundle & TestCategory != MonoSymbolicate & TestCategory != PackagesConfig & TestCategory != StaticProject & TestCategory != SystemApplication'
-  #TODO: Remove package var overrides once we are building against a .NET 8 SDK and can push to the dotnet8 feed
-- name: PushXAPackages
-  value: false
-- name: PushXAPackageInfoToMaestro
-  value: false
 - ${{ if eq(variables['Build.DefinitionName'], 'Xamarin.Android-Private') }}:
   - group: AzureDevOps-Artifact-Feeds-Pats
   - group: DotNet-MSRC-Storage
   - name: DotNetFeedCredential
-    value: dotnet7-internal-dnceng-internal-feed
+    value: dotnet8-internal-dnceng-internal-feed
 - ${{ if ne(variables['Build.DefinitionName'], 'Xamarin.Android-Private') }}:
   - name: DotNetFeedCredential
-    value: dnceng-dotnet7
+    value: dnceng-dotnet8
 - ${{ if and(or(eq(variables['Build.DefinitionName'], 'Xamarin.Android'), eq(variables['Build.DefinitionName'], 'Xamarin.Android-Private')), ne(variables['Build.Reason'], 'PullRequest')) }}:
   - name: MicroBuildSignType
     value: Real