Update db-backup workflow to include environment input

.github/workflows/db-backup.yml

@@ -4,13 +4,20 @@ on:
   schedule:
     - cron: "0 10 * * 1" # At 10:00 on Monday.
   workflow_dispatch:
+    inputs:
+      environment:
+        description: The Github environment to load secrets from
+        type: string  
+        required: true
 
 defaults:
   run:
     shell: bash
 
 jobs:
   build-and-run-backups:
+    # If the execution is triggered by a schedule, the environment is production
+    environment: ${{ inputs.environment || 'production' }}
     name: Backup
     runs-on: ubuntu-latest