SMTP Environment Variables (#111)

Follow up to #97 

## Changes

<!-- What changes did you make? -->

- add env vars for dummy gmail account for email notifications to CI

## Testing

<!-- How did you confirm your changes worked? -->

- test email sending via preview branch (e.g. demote a HL/promote a RS)

## Confirmation of Change

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instructions on how to see the change. -->

N/A

.github/workflows/build-and-deploy.yml

@@ -47,6 +47,8 @@ jobs:
           echo MONGODB_URI=${{ secrets.MONGODB_URI }} >> .env
           echo FRONTEND_ORIGIN=${{ vars.FRONTEND_ORIGIN }} >> .env
           echo FIREBASE=${{ secrets.FIREBASE }} >> .env
+          echo GMAILUSER=${{ secrets.GMAILUSER }} >> .env
+          echo GMAILPASS=${{ secrets.GMAILPASS }} >> .env
       - name: Deploy to Firebase
         uses: FirebaseExtended/action-hosting-deploy@v0
         with: