add env vars in github workflows

Author: AlaaElattar

.github/workflows/coverage.yaml

@@ -43,6 +43,8 @@ jobs:
       - name: Run unit tests
         env:
           MNEMONIC: ${{ secrets.MNEMONIC }}
+          LINK: ${{ secrets.LINK }}
+          SIGN_TYPE: ${{ secrets.SIGN_TYPE}}
         run: |
           melos exec rm -rf coverage
           melos run unit_test