Update actions/checkout action to v4

Author: bst27

.github/workflows/go.yml

@@ -20,7 +20,7 @@ jobs:
       id: go
 
     - name: Check out code into the Go module directory
-      uses: actions/checkout@v2
+      uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
 
     - name: Get dependencies
       run: |