Revert "Update exploration-build.yml for Azure Pipelines"

This reverts commit 88e3bed9.

build/azure-pipelines/exploration-build.yml

-pool:
-  vmImage: 'Ubuntu-16.04'
-
 trigger:
   branches:
-    include: ['master', 'release/*']
+    include: ['master']
 pr:
   branches:
-    include: ['master', 'release/*']
+    include: ['master']
 
 steps:
 - task: NodeTool@0
   inputs:
     versionSpec: "10.15.1"
 
-- task: AzureKeyVault@1
-  displayName: 'Azure Key Vault: Get Secrets'
-  inputs:
-    azureSubscription: 'vscode-builds-subscription'
-    KeyVaultName: vscode
-
 - script: |
     set -e
 
     cat << EOF > ~/.netrc
-    machine github.com
-    login vscode
-    password $(github-distro-mixin-password)
-    EOF
 
     git config user.email "vscode@microsoft.com"
     git config user.name "VSCode"
 
-    git remote add distro "https://github.com/$VSCODE_MIXIN_REPO.git"
-    git fetch distro
-
-    # Push master branch into oss/master
-    git push distro origin/master:refs/heads/oss/master
-
-    # Push every release branch into oss/release
-    git for-each-ref --format="%(refname:short)" refs/remotes/origin/release/* | sed 's/^origin\/\(.*\)$/\0:refs\/heads\/oss\/\1/' | xargs git push distro
+    git checkout origin/ben/electron-test
+    git merge origin/master
 
-    git merge $(node -p "require('./package.json').distro")
+    # Push master branch into exploration branch
+    git push origin HEAD:ben/electron-test
 
-  displayName: Sync & Merge Distro
+  displayName: Sync & Merge Exploration