Add support for PublishSymbols@2 task (10 failures)

[samsmithnz]

• 7 failures on Feb-2021 (including one PublishSymbols@1 task)
• 2 failures in Apr-2021
• 1 failure in May-2021

https://docs.microsoft.com/en-us/azure/devops/pipelines/tasks/build/index-sources-publish-symbols?view=azure-devops