Fix linter errors

Signed-off-by: Daniel Mikusa <[email protected]>

golangci.yaml

@@ -26,3 +26,10 @@ linters:
 linters-settings:
   goimports:
     local-prefixes: github.com/buildpacks/libcnb
+  revive:
+    rules:
+      - name: dot-imports
+        arguments:
+          - allowedPackages:
+              - github.com/onsi/ginkgo/v2
+              - github.com/onsi/gomega

internal/directory_contents.go

@@ -32,7 +32,7 @@ type DirectoryContents struct {
 func (d DirectoryContents) Get() ([]string, error) {
 	var contents []string
 
-	if err := filepath.Walk(d.Path, func(path string, info os.FileInfo, err error) error {
+	if err := filepath.Walk(d.Path, func(path string, _ os.FileInfo, err error) error {
 		if err != nil {
 			return err
 		}