Stop using Api Key in Create-ApiReview script

We can follow the same pattern as used in https://github.com/Azure/azure-sdk-tools/pull/13235

And apply those changes to https://github.com/microsoft/typespec/blob/main/eng/emitters/scripts/Create-APIReview.ps1

Also need to update https://github.com/microsoft/typespec/blob/main/eng/emitters/pipelines/templates/steps/create-apireview.yml