Notes about Node16 migration (#16477)
Notes about Node16 migration (#16477)

* docs about Node16 migration

* add agent version

* updated according to comments

Co-authored-by: Andrey Ivanov <f46068be069c8e52c4c6d808e7575bc4d441da0d@microsoft.com>
Microsoft/vso-agent-tasks,Microsoft/vso-agent-tasks,Microsoft/vso-agent-tasks