CodeGen from PR 12639 in Azure/azure-rest-api-specs

[Service Fabric Managed Clusters] 2021-01-01-preview (Azure#12639)

* add servicefabricmanagedclusters folder with 2020-01-01-preview specs

* update swagger with version 2021-01-01-preview

* fix validation errors

* add required systemData param in resources and add missing formats

* fix formats

* add ipv4Address, fix clusterCertificateThumbprints and descriptions

* fix patch (only tags), remvoe clusterVersions, fix nsg

* remove unnecessary example

* fix patch descriptions and full arm resource id for type version

* fix sdk profile name

* fix lastModifiedAt description and python sdk path

* add missing applicationTypeVersionsCleanupPolicy

* fix location description and app example params

* remove after_scripts for python sdk

Co-authored-by: Alfredo Santamaria Gomez <alsantam@microsoft.com>