CodeGen from PR 15939 in Azure/azure-rest-api-specs

[Hub Generated] Review request for Microsoft.LabServices to add version preview/2021-10-01-preview (#15939)

* Adds base for updating Microsoft.LabServices from version stable/2018-10-15 to version 2021-10-01-preview

* Updates readme

* Updates API version in new specs and examples

* remove 2018 api spec files

* add 2021-10-01-preview spec files from generation

* update preview api files in readme.md input

* update 2020 -> 2021 in new api version in readme

* spelling fixes

* fix object body mutability

* add type:object where missing

* added default error response

* tracker resource operation naming and description adding

* fix shutdownOnIdleEnabled in examples

* fix shutdownonIdle enum in examples

* examples update username to adminUser object and remove locations from vmprofile

* fix examples for vmprofile

* rest of model validaiton fixes

* prettier fix

* removed skus api from 2021-10-01 version since it's not finished

* fix operationresults

* small images fix

Co-authored-by: Nick Depinet <ndepinet@microsoft.com>

Author: SDKAuto