Update pre-release pipeline (#398)

* Dont use update_ext_version in pre-release

* Add flag for standardizedVersioning

build/azure-pipeline.pre-release.yml

@@ -28,6 +28,7 @@ extends:
   template: azure-pipelines/extension/pre-release.yml@templates
   parameters:
     l10nSourcePaths: ./src
+    standardizedVersioning: true
     buildPlatforms:
       - name: Linux
         vsceTarget: ''
@@ -81,9 +82,6 @@ extends:
         env:
           VSCETARGET: ${{ variables.VSCETARGET }}
 
-      - script: python ./build/update_ext_version.py --for-publishing
-        displayName: Update build number
-
       - script: npm run package
         displayName: Build extension