Attempt at fixing wait for new package appearing in PyPI index.

.github/workflows/publish-rc.yml

@@ -53,8 +53,17 @@ jobs:
     - name: Install from testpypi and import.
       run: |
         i=0
-        while (($i<120)) && [[ ! $(curl --max-time 120 -s https://test.pypi.org/pypi/${{ env.PACKAGE_NAME }}/json | jq -r '.releases | keys[]') =~ (^|[[:space:]])${{ env.VERSION }}($|[[:space:]]) ]];\
-          do echo waiting for package to appear in test index, sleeping 5s; sleep 5s; let i++; done
+        n=60
+        exists=0
+        while [ $i -lt $n ] && [ $exists -eq 0 ]; do
+            if curl -s https://test.pypi.org/pypi/${{ env.PACKAGE_NAME }}/json | jq -e '.releases | has("${{ env.VERSION }}")' &> /dev/null; then
+                exists=1
+            else
+                ((i++))
+                echo "$i/$n Waiting for package to appear in test index, sleeping 5s.
+                sleep 5s
+            fi
+        done
         pip install --no-cache-dir --index-url https://test.pypi.org/simple ${{ env.PACKAGE_NAME }}==${{ env.VERSION }} --no-deps
         pip install -r requirements.txt
         python -c 'import ${{ env.MODULE_NAME }};print(${{ env.MODULE_NAME }}.__version__)'