fix(push): read curl payload from file

entrypoint.sh

@@ -7,15 +7,19 @@ tectonic $1
 
 OUTPUT_PDF="${1%.*}.pdf"
 
-STATUSCODE=$(curl --silent --output /dev/stderr --write-out "%{http_code}" -i -X PUT -H "Authorization: token $GITHUB_TOKEN" -d '{
+echo '{
   "message": "'"update $OUTPUT_PDF"'",
   "committer": {
     "name": "Tectonic Action",
     "email": "[email protected]"
   },
   "content": "'"$(base64 -w 0 $OUTPUT_PDF)"'",
   "sha": '$(curl -X GET https://api.github.com/repos/vinay0410/webpage/contents/$OUTPUT_PDF | jq .sha)'
-}' https://api.github.com/repos/vinay0410/webpage/contents/$OUTPUT_PDF)
+}' >> payload.json
+
+STATUSCODE=$(curl --silent --output /dev/stderr --write-out "%{http_code}" \
+            -i -X PUT -H "Authorization: token $GITHUB_TOKEN" -d @payload.json \
+            https://api.github.com/repos/vinay0410/webpage/contents/$OUTPUT_PDF)
 
 if [ $((STATUSCODE/100)) -ne 2 ]; then
   echo "Github's API returned $STATUSCODE"