Bump actions/checkout from v2.3.1 to v2.3.4

Bumps [actions/checkout](https://github.com/actions/checkout) from v2.3.1 to v2.3.4.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v2.3.1...5a4ac90)

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

.github/workflows/build.yaml

@@ -6,6 +6,6 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v2.3.1
+    - uses: actions/checkout@v2.3.4
     - run: touch index.bs
     - run: make online=1

.github/workflows/deploy.yaml

@@ -10,7 +10,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: Checkout
-      uses: actions/checkout@v2.3.1
+      uses: actions/checkout@v2.3.4
 
     - name: Build
       run: |