chore(deps): bump actions/checkout from 4 to 5

Bumps [actions/checkout](https://github.com/actions/checkout) from 4 to 5.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v4...v5)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '5'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

.github/workflows/ci.yaml

@@ -23,7 +23,7 @@ jobs:
             install-rg: choco install nodejs-lts curl
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
 
       - uses: rhysd/action-setup-vim@v1
         with:

.github/workflows/update-copilot-nodejs.yaml

@@ -14,7 +14,7 @@ jobs:
     if: github.repository == 'zbirenbaum/copilot.lua'
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: Create directory
         run: |

.github/workflows/vimdocgen.yml

@@ -16,7 +16,7 @@ jobs:
     runs-on: ubuntu-latest
     name: Convert Markdown to Vimdoc
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - uses: kdheepak/panvimdoc@main
         with:
           vimdoc: "copilot"