Remove references in live tests to hardcoded variable group secrets

As a follow-on to https://github.com/Azure/azure-sdk-tools/issues/1050, we need to update all secret references in live test `tests.yml` files to use the subscription configuration/cloud config only. Values are still marked as secret that shouldn't be because they exist in the devops variable group. We also need to remove these secrets from all variable groups and the live test secrets keyvault.

The following devops keyvault secret variables that need to be removed:

```
provisioner-aad-id
provisioner-aad-secret
provisioner-aad-tenant
provisioner-subscription
provisioner-test-app-id
aad-azure-sdk-test-client-id
aad-azure-sdk-test-client-oid
aad-azure-sdk-test-tenant-id
aad-azure-sdk-test-client-secret
provisioner-aad-id-cn
provisioner-aad-id-gov
provisioner-aad-secret-cn
provisioner-aad-secret-gov
provisioner-aad-tenant-gov
provisioner-subscription-gov
provisioner-subscription-cn
provisioner-aad-tenant-cn
azure-subscription-id
azure-subscription-id-cn
azure-subscription-id-gov
aad-azure-sdk-test-client-id-cn
aad-azure-sdk-test-client-id-gov
aad-azure-sdk-test-client-oid-cn
aad-azure-sdk-test-client-oid-gov
aad-azure-sdk-test-client-secret-cn
aad-azure-sdk-test-client-secret-gov
aad-azure-sdk-test-tenant-id-cn
aad-azure-sdk-test-tenant-id-gov
aad-azure-sdk-test-authority-host
aad-azure-sdk-test-authority-host-cn
aad-azure-sdk-test-authority-host-gov
aad-azure-sdk-test-authority-uri
aad-azure-sdk-test-authority-uri-cn
aad-azure-sdk-test-authority-uri-gov
azure-subscription-preview-id
provisioner-keyvault-name
```