fix: remove unused imports in test files (ESLint)

- validators.test.js: remove unused execSync (only execFileSync used)
- skill-create-output.test.js: remove unused path module

tests/scripts/skill-create-output.test.js

@@ -7,8 +7,6 @@
  */
 
 const assert = require('assert');
-const path = require('path');
-
 // Import the module
 const { SkillCreateOutput } = require('../../scripts/skill-create-output');