DP-842 - use venv for b2 upload

Author: rhryckewicz

.github/workflows/ci_cd.yml

@@ -74,7 +74,9 @@ jobs:
         if: github.ref == 'refs/heads/master' || github.ref == 'refs/heads/api-v2' || github.ref == 'refs/heads/7.x'
         # upload to b2 (if credentials are provided, as they will be for backblaze's builds, but not pull requests)
         # This should be using python 3.8
-        run: $GITHUB_WORKSPACE/maybe_upload_build_results ${{ env.OUTPUT_ZIP }}
+        run: |
+          source env/bin/activate
+          $GITHUB_WORKSPACE/maybe_upload_build_results ${{ env.OUTPUT_ZIP }}
 
       - name: Check GitHub Pages status
         if: github.ref == 'refs/heads/master'