Bring back cloud build numbers

Author: AArnott

azure-pipelines/build.yml

@@ -12,6 +12,10 @@ jobs:
     fetchDepth: 0 # avoid shallow clone so nbgv can do its work.
     clean: true
   - template: install-dependencies.yml
+
+  - powershell: '& (./azure-pipelines/Get-nbgv.ps1) cloud'
+    displayName: Set build number
+
   - template: dotnet.yml
     parameters:
       RunTests: ${{ parameters.RunTests }}