Bump actions/checkout from 2 to 2.3.4

Bumps [actions/checkout](https://github.com/actions/checkout) from 2 to 2.3.4.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v2...v2.3.4)

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

Author: dependabot[bot]

.github/workflows/ci.yaml

@@ -42,7 +42,7 @@ jobs:
         run: echo "date=$(date -u +%Y-%m-%dT%H%M%SZ)" >> $GITHUB_ENV
       -
         name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v2.3.4
       -
         name: Set up QEMU
         uses: docker/setup-qemu-action@v1.1.0

.github/workflows/lint.yaml

@@ -14,7 +14,7 @@ jobs:
 
     steps:
       - name: Check out the codebase.
-        uses: actions/checkout@v2
+        uses: actions/checkout@v2.3.4
 
       - name: Hadolint Action
         # You may pin to the exact commit or the version.
@@ -29,7 +29,7 @@ jobs:
 
     steps:
       - name: Check out the codebase.
-        uses: actions/checkout@v2
+        uses: actions/checkout@v2.3.4
 
       - name: Set up Python 3.
         uses: actions/setup-python@v2.2.2