handle missing pdf cache key

Author: josh-heyer

.github/workflows/deploy-to-netlify.yml

@@ -52,6 +52,7 @@ jobs:
           key: ${{ inputs.pages-cache-key }}
 
       - name: Pull PDF cache
+        if: ${{ inputs.pdf-cache-key }}
         uses: actions/cache/restore@v4
         with:
           path: |