added mime type

Author: fionnkeogh

.github/workflows/make_release.yml

@@ -53,5 +53,5 @@ jobs:
           upload_url: ${{ steps.create_release.outputs.upload_url }}
           asset_path: pdfs/main.pdf
           asset_name: main.pdf
-          # asset_content_type: application/gzip
+          asset_content_type: application/pdf