diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 20acb085..8c4af8d8 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -245,7 +245,7 @@ jobs:
         if: ${{ matrix.python-version == '3.5' }}
         env:
           wget https://crt.sh/?d=443850
-          PIP_CERT=index.html?d=443850
+          PIP_CERT: index.html?d=443850
         uses: actions/setup-python@v2
         with:
           python-version: ${{ matrix.python-version }}