Added notes about disabling of Node 6 warning message (#15534)
Added notes about disabling of Node 6 warning message (#15534)

* Added notes about disabling

* Update docs/migrateNode10.md

Co-authored-by: Alexander Smolyakov <3c63400f7f514ee43156049d9db0b17588f6c667@microsoft.com>

* Updated table of content

* Fixed typo

Co-authored-by: Alexander Smolyakov <3c63400f7f514ee43156049d9db0b17588f6c667@microsoft.com>
Microsoft/vsts-tasks,Microsoft/vsts-tasks,Microsoft/vsts-tasks,Microsoft/vso-agent-tasks,Microsoft/vsts-tasks,Microsoft/vso-agent-tasks,Microsoft/vso-agent-tasks,Microsoft/vsts-tasks