CodeGen from PR 16156 in Azure/azure-rest-api-specs

[Hub Generated] Review request for Microsoft.KeyVault to add version stable/2021-10-01 and preview/2021-11-01-preview (#16156)

* Adds base for updating Microsoft.KeyVault from version preview/2021-06-01-preview to version 2021-10-01

* Updates readme

* Updates API version in new specs and examples

* Keys.json done

* keyvault.json done

* Readd systemdata

* Fix keyvault.json

* Add type: object to missing definitions except MHSMs.

* Fix

* Fix

* Add type object to MHSM

* Remove 404 responses from new api-version

* Merge new preview version 2021-11-01-preview

* Readd 2021-10-01 to readme

* Add changes for key rotation to new preview api version.

* Add x-ms-enum as per request from SDK team

* Fix duplicated value

Author: SDKAuto