Update golangci-lint-action version and simplify cache skipping

Updated the version of golangci/golangci-lint-action used in GitHub Actions CI workflow from v3 to v6. Also, replaced the skip-build-cache and skip-pkg-cache options with the simpler skip-cache option.

.github/workflows/ci.yml

@@ -10,17 +10,16 @@ jobs:
     name: Validate source code with linters
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Set up Go
-        uses: actions/setup-go@v3
+        uses: actions/setup-go@v5
         with:
           go-version-file: 'go.mod'
       - name: Run lint
-        uses: golangci/golangci-lint-action@v3
+        uses: golangci/golangci-lint-action@v6
         with:
           version: latest
-          skip-build-cache: true
-          skip-pkg-cache: true
+          skip-cache: true
 
   test:
     name: Run the tests suite
@@ -30,9 +29,9 @@ jobs:
       matrix:
         os: [ ubuntu-latest, macOS-latest, windows-latest ]
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Set up Go
-        uses: actions/setup-go@v3
+        uses: actions/setup-go@v5
         with:
           go-version-file: 'go.mod'
       - name: Run tests with coverage

internal/engine/tokenmutator_test.go

@@ -1,5 +1,5 @@
 /*
- * Copyright 2022 The Gremlins Authors
+ * Copyright 2024 The Gremlins Authors
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
@@ -41,7 +41,7 @@ func TestMutantApplyAndRollback(t *testing.T) {
 	filePath := "sourceFile.go"
 	fileFullPath := filepath.Join(workdir, filePath)
 
-	err := os.WriteFile(fileFullPath, []byte(rollbackWant), os.ModePerm)
+	err := os.WriteFile(fileFullPath, []byte(rollbackWant), 0600)
 	if err != nil {
 		t.Fatal(err)
 	}