ci(github): use unary plus operator in mixed-inputs.yml

Author: remarkablemark

.github/workflows/mixed-inputs.yml

@@ -20,6 +20,6 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: Send greeting
-      run: echo $MESSAGE ${{ toJSON(inputs.name) }} ${{ fromJSON('["", "🥳"]')[inputs.use-emoji == 'true'] }}
+      run: echo $MESSAGE ${{ toJSON(inputs.name) }} ${{ fromJSON('["", "🥳"]')[+inputs.use-emoji] }}
       env:
         MESSAGE: ${{ inputs.message }}