Update ADO image

[isra-fel]

Description

Update ADO image from vs2017-win2016 to windows-2019 as win2016 is being removed.

Fix #16275

Test

• CI of this pipeline must pass
• Daily smoke test pipeline must pass: https://dev.azure.com/azure-sdk/internal/_build/results?buildId=1194925&view=results

Checklist

• I have read the Submitting Changes section of CONTRIBUTING.md
• The title of the PR is clear and informative
• The appropriate ChangeLog.md file(s) has been updated:
  • For any service, the ChangeLog.md file can be found at src/{{SERVICE}}/{{SERVICE}}/ChangeLog.md
  • A snippet outlining the change(s) made in the PR should be written under the ## Upcoming Release header -- no new version header should be added
• The PR does not introduce breaking changes
• If applicable, the changes made in the PR have proper test coverage
• For public API changes to cmdlets:
  • a cmdlet design review was approved for the changes in this repository (Microsoft internal only)
    • {Please put the link here}
  • the markdown help files have been regenerated using the commands listed here

[isra-fel]

/azp run azure-powershell - windows-powershell

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[isra-fel]

/azp run azure-powershell - security-tools

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[BethanyZhou]

LGTM

[isra-fel]

/azp run azure-powershell - powershell-core

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[isra-fel]

/azp run /azp run azure-powershell - powershell-core

[azure-pipelines]

No pipelines are associated with this pull request.

[isra-fel]

/azp run azure-powershell - powershell-core

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).