Appveyor: fix version specifier syntax
@@ -22,7 +22,7 @@ install:
- cinst imagemagick -y
# TODO: remove --allow-empty-checksums when unrar offers a proper checksum
- cinst unrar -y --allow-empty-checksums
- - "%PYTHON%/Scripts/pip.exe install tox<=3.8.1"
+ - '%PYTHON%/Scripts/pip.exe install "tox<=3.8.1"'
- "%PYTHON%/Scripts/tox.exe -e %TOX_ENV% --notest"
test_script:
