Update Vim to v9.1.0065

Use the same version as vim-jp/vimdoc-ja-working.

Author: k-takata

.github/workflows/generate.yml

@@ -28,7 +28,7 @@ jobs:
       - name: Setup Vim
         uses: thinca/action-setup-vim@v2
         with:
-          vim_version: 'v8.2.0020'
+          vim_version: 'v9.1.0065'
           vim_type: 'Vim'
       - name: Generate new document
         run: |