PLT-746 Fix if statement in "promote" workflow (#1415)

## 🎫 Ticket

[PLT-746](https://jira.cms.gov/browse/PLT-746)

## 🛠 Changes

"fi" was added at the end of set environment variable statement

## ℹ️ Context

ab2d team is trying to deploy some code to "prod-test" and looks like
there are errors with existing code syntax in the. "promote" work flow .

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## 🧪 Validation

Link to a successful manually trigger
https://github.com/CMSgov/ab2d/actions/runs/11666218254

---------

Co-authored-by: Maboh Christopher <[email protected]>

.github/workflows/promote.yml

@@ -47,6 +47,7 @@ jobs:
             echo "TAG_PREFIX=ab2d-prod-test" >> $GITHUB_ENV
           else
             echo "TAG_PREFIX=ab2d-$DEPLOYMENT_ENV" >> $GITHUB_ENV
+          fi
 
       - name: Retag images in ECR
         env: