Bump actions/checkout from 2.3.5 to 2.4.0 (#50)

Bumps [actions/checkout](https://github.com/actions/checkout) from 2.3.5 to 2.4.0.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v2.3.5...v2.4.0)

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

Signed-off-by: dependabot[bot] <support@github.com>

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

Author: dependabot[bot]

.github/workflows/github.prs.combine.yml

@@ -93,7 +93,7 @@ jobs:
             console.log('Combined: ' + combined);
             return combined
       # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
-      - uses: actions/checkout@v2.3.5
+      - uses: actions/checkout@v2.4.0
         with:
           fetch-depth: 0
           token: ${{ secrets.GH_TOKEN_PLUSW }}

.github/workflows/node.test.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v2.3.5
+    - uses: actions/checkout@v2.4.0
     - name: Use Node.js 14.x
       uses: actions/setup-node@v2.4.1
       with:

.github/workflows/pages.build.yml

@@ -8,7 +8,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: Checkout
-      uses: actions/checkout@v2.3.5
+      uses: actions/checkout@v2.4.0
 
     - name: vuepress-deploy
       uses: jenkey2011/vuepress-deploy@master