Update actions/checkout action to v4

Author: renovate[bot]

.github/workflows/lint.yml

@@ -10,7 +10,7 @@ jobs:
   lint:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
     - name: Determine Go version from go.mod
       run: echo "GO_VERSION=$(grep "go 1." go.mod | cut -d " " -f 2)" >> $GITHUB_ENV
     - uses: actions/setup-go@v2

.github/workflows/test.yml

@@ -12,7 +12,7 @@ jobs:
   test:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
     - name: Determine Go version from go.mod
       run: echo "GO_VERSION=$(grep "go 1." go.mod | cut -d " " -f 2)" >> $GITHUB_ENV
     - uses: actions/setup-go@v2