[AutoPR apimanagement/resource-manager] Remove readonly attribute from identities collection in users

[AutorestCI]

Created to sync Azure/azure-rest-api-specs#4442

[azuresdkciprbot]

Ruby Build Drop - Direct download

The Gem file (zipped version) could be downloaded here.

Installation instructions

1. Download the Build Drop zip file: azure-sdk-for-ruby_pr1896.tar.gz.
2. Unzip the file using the following command: tar -xzf azure-sdk-for-ruby_pr1896.tar.gz.
3. In the Gemfile of your project, add reference to your gem. For example, if your gem is azure_mgmt_locks, the reference would be: gem 'azure_mgmt_locks', '<VERSION_OF_GEM>', path: '<UNZIPPED_PATH>/management/azure_mgmt_locks/pkg'

Note: VERSION_OF_GEM can be found from the name of the gem file. For example, if the name of the gemfile is azure_mgmt_locks-0.17.1.gem, the VERSION_OF_GEM will be 0.17.1.

[AutorestCI]

This PR has been merged into #1898