Update all provisionator call sites to use AUTH_TOKEN_GITHUB_COM (#16511)

This introduces changes to ensure that the Github token is available at all provisionator invocations so that when we need to flip to using dl.internalx.com, there are no breakages.

tools/devops/automation/templates/build/build.yml

@@ -60,6 +60,8 @@ steps:
   inputs:
     provisioning_script: $(Build.SourcesDirectory)/xamarin-macios/tools/devops/provision-brew-packages.csx
     provisioning_extra_args: '-vvvv'
+  env:
+    AUTH_TOKEN_GITHUB_COM: ${{ parameters.gitHubToken }}
   timeoutInMinutes: 30
   enabled: true
   continueOnError: true # brew installation can be temperamental, and things usually work even if the installation fail.
@@ -73,6 +75,8 @@ steps:
   inputs:
     provisioning_script: $(Build.SourcesDirectory)/xamarin-macios/tools/devops/build-provisioning.csx
     provisioning_extra_args: '-vvvv'
+  env:
+    AUTH_TOKEN_GITHUB_COM: ${{ parameters.gitHubToken }}
   timeoutInMinutes: 250
 
 # Use the env variables that were set by the label parsing in the configure step

tools/devops/automation/templates/mac/build.yml

@@ -118,6 +118,8 @@ steps:
   inputs:
     provisioning_script: $(Build.SourcesDirectory)/xamarin-macios/tools/devops/provision-brew-packages.csx
     provisioning_extra_args: '-vvvv'
+  env:
+    AUTH_TOKEN_GITHUB_COM: $(GitHub.Token)
   timeoutInMinutes: 30
   enabled: false
 
@@ -151,6 +153,8 @@ steps:
   inputs:
     provisioning_script: $(Build.SourcesDirectory)/xamarin-macios/tools/devops/mac-tests-provisioning.csx
     provisioning_extra_args: '-vvvv'
+  env:
+    AUTH_TOKEN_GITHUB_COM: $(GitHub.Token)
   timeoutInMinutes: 250
 
 # Executed ONLY if we want to clear the provisionator cache.

tools/devops/automation/templates/tests/build.yml

@@ -161,6 +161,8 @@ steps:
   inputs:
     provisioning_script: $(System.DefaultWorkingDirectory)/xamarin-macios/tools/devops/device-tests-provisioning.csx
     provisioning_extra_args: '-vvvv'
+  env:
+    AUTH_TOKEN_GITHUB_COM: ${{ parameters.gitHubToken }}
   timeoutInMinutes: 250
 
 - bash: |
@@ -173,6 +175,8 @@ steps:
   inputs:
     provisioning_script: $(Build.SourcesDirectory)/xamarin-macios/tools/devops/mac-tests-provisioning.csx
     provisioning_extra_args: '-vvvv'
+  env:
+    AUTH_TOKEN_GITHUB_COM: ${{ parameters.gitHubToken }}
   timeoutInMinutes: 250
 
 - bash: |