ci: fixup to #586, neovim-stable on windows

Author: wookayin

.github/workflows/test.yml

@@ -33,7 +33,7 @@ jobs:
           { python-version: '3.12', neovim-version: 'stable' },
           { python-version: '3.11' },
           { python-version: '3.10' },
-          # for python 3.7~3.9, use older version of OS (ubuntu-20.04 and macos-12)
+          # for python 3.7~3.9, use older version of OS (ubuntu-20.04 and macos-13)
           { python-version: '3.9', ubuntu: '20.04', macos: '13' },
           { python-version: '3.8', ubuntu: '20.04', macos: '13' },
           { python-version: '3.7', ubuntu: '20.04', macos: '13' },
@@ -76,7 +76,7 @@ jobs:
     - name: install neovim (Windows)
       if: runner.os == 'Windows'
       run: |
-        curl -LO "https://github.com/neovim/neovim/releases/download/nightly/nvim-win64.zip"
+        curl -LO "https://github.com/neovim/neovim/releases/download/${{ matrix.config.neovim-version || 'nightly' }}/nvim-win64.zip"
         unzip nvim-win64.zip
         nvim-win64/bin/nvim --version