Update actions/checkout action to v2.6.0

Author: renovate[bot]

.github/workflows/ci.yaml

@@ -45,7 +45,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v2.3.4
+        uses: actions/checkout@v2.6.0
 
       # Define if tests and push should be run against which versions/platforms
       - name: Prepare
@@ -106,7 +106,7 @@ jobs:
       - tag-does-not-exist
     steps:
       - name: Checkout
-        uses: actions/checkout@v2.3.4
+        uses: actions/checkout@v2.6.0
 
       - name: Set up QEMU
         uses: docker/setup-qemu-action@v1.2.0

.github/workflows/lint.yaml

@@ -14,7 +14,7 @@ jobs:
 
     steps:
       - name: Check out the codebase.
-        uses: actions/checkout@v2.3.4
+        uses: actions/checkout@v2.6.0
 
       - 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@v2.3.4
+        uses: actions/checkout@v2.6.0
 
       - name: Set up Python 3.
         uses: actions/setup-python@v2.2.2