ci: bump leafo/gh-actions-lua from 11 to 12 (#4097)

Bumps [leafo/gh-actions-lua](https://github.com/leafo/gh-actions-lua) from 11 to 12.
- [Release notes](https://github.com/leafo/gh-actions-lua/releases)
- [Commits](leafo/gh-actions-lua@v11...v12)

---
updated-dependencies:
- dependency-name: leafo/gh-actions-lua
  dependency-version: '12'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/test.yml

@@ -23,7 +23,7 @@ jobs:
           neovim: true
           version: ${{ matrix.nvim_version }}
 
-      - uses: leafo/gh-actions-lua@v11
+      - uses: leafo/gh-actions-lua@v12
         with:
           luaVersion: "luajit-openresty"
       - uses: leafo/gh-actions-luarocks@v5