Fix production deployments failing due to missing -global suffix in staging registry reference (#803)

### Summary & Motivation

Fix production container deployments failing to import images from the
staging registry. The `STAGING_REGISTRY_ID` in `_deploy-container.yml`
was missing the `-global` suffix in the resource group name, a bug
introduced in #793 when the global resource group was renamed. This is
currently preventing all deployments to production.

- Update resource group reference from `{prefix}-stage` to
`{prefix}-stage-global` to match the actual location of the staging
container registry

### Checklist

- [x] I have added tests, or done manual regression tests
- [x] I have updated the documentation, if necessary

Author: tjementum

.github/workflows/_deploy-container.yml

@@ -71,7 +71,7 @@ jobs:
       - name: Import Container Image from Staging to Production
         if: inputs.azure_environment == 'prod'
         run: |
-          STAGING_REGISTRY_ID="/subscriptions/${{ vars.STAGING_SUBSCRIPTION_ID }}/resourceGroups/${{ env.UNIQUE_PREFIX }}-stage/providers/Microsoft.ContainerRegistry/registries/${{ env.UNIQUE_PREFIX }}stage"
+          STAGING_REGISTRY_ID="/subscriptions/${{ vars.STAGING_SUBSCRIPTION_ID }}/resourceGroups/${{ env.UNIQUE_PREFIX }}-stage-global/providers/Microsoft.ContainerRegistry/registries/${{ env.UNIQUE_PREFIX }}stage"
 
           az acr import \
             --name ${{ env.UNIQUE_PREFIX }}${{ env.ENVIRONMENT }} \