chore: set license of eslint-plugin-cdk (#14720)

Fixes #14594

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*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

Author: Elad Ben-Israel

tools/eslint-plugin-cdk/package.json

@@ -32,5 +32,5 @@
   },
   "keywords": [],
   "author": "",
-  "license": "ISC"
+  "license": "Apache-2.0"
 }