Update actions/checkout action to v4

Author: renovate[bot]

.github/workflows/ci.yml

@@ -14,7 +14,7 @@ jobs:
         - "1.22"
     steps:
       - name: Check out source code
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Set up Go
         uses: actions/setup-go@v5

.github/workflows/generate.yml

@@ -14,7 +14,7 @@ jobs:
         - "1.22"
     steps:
       - name: Check out source code
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Set up Go
         uses: actions/setup-go@v5

.github/workflows/lint.yml

@@ -14,7 +14,7 @@ jobs:
         - "1.22"
     steps:
       - name: Check out source code
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Set up Go
         uses: actions/setup-go@v5

.github/workflows/tidy.yml

@@ -14,7 +14,7 @@ jobs:
         - "1.22"
     steps:
       - name: Check out source code
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Set up Go
         uses: actions/setup-go@v5