Merge pull request #2634 from MicrosoftDocs/repo_sync_working_branch

Confirm merge from repo_sync_working_branch to master to sync with https://github.com/MicrosoftDocs/azure-devops-docs (branch master)

Author: Taojunshen

docs/pipelines/process/run-number.md

@@ -26,7 +26,7 @@ You can use a combination of tokens, variables, and underscore characters.
 name: $(TeamProject)_$(Build.DefinitionName)_$(SourceBranchName)_$(Date:yyyyMMdd)$(Rev:.r)
 
 steps:
-  - script: echo $(Build.BuildNumber) # outputs customized build number like project_def_master_20200828.1
+  - script: echo '$(Build.BuildNumber)' # outputs customized build number like project_def_master_20200828.1
 ```
 
 ::: moniker-end