No luck with /proc/self/fd/2 either

deploy.sh

@@ -37,10 +37,10 @@ git remote set-url origin "git@gitlab.epfl.ch:idevelop/howtogitlabrunner.git"
 git push -f --tags
 echo "END OF PUSH"
 
-stderr=/proc/self/fd/2
+tee_stderr=cat  # Permission denied on /proc/self/fd/2, wat?
 
 echo "BEGIN UPLOAD"
-UPLOADED_FILE_URL="$(curl --request POST --header "Private-Token: ${MY_TOKEN}" --form "file=@README.pdf" "https://gitlab.epfl.ch/api/v4/projects/$PROJECT_ID/uploads" | tee $stderr | jq -r .url)"
+UPLOADED_FILE_URL="$(curl --request POST --header "Private-Token: ${MY_TOKEN}" --form "file=@README.pdf" "https://gitlab.epfl.ch/api/v4/projects/$PROJECT_ID/uploads" | $tee_stderr | jq -r .url)"
 echo "END UPLOAD"
 
 echo "BEGIN POST RELEASE"
@@ -50,7 +50,7 @@ for retry in $(seq 1 5); do
         --header "Private-Token: ${MY_TOKEN}" \
         --data '{"name": "New README release", "tag_name": "'${RELEASE_V}'", "description": "Release with the PDF [README.pdf]('${UPLOADED_FILE_URL}')"}' \
         "https://gitlab.epfl.ch/api/v4/projects/'${PROJECT_ID}'/releases" \
-        | tee $stderr | jq -e ".created_at"
+        | $tee_stderr | jq -e ".created_at"
     then
         break
     else