package.json: add private: true

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package.json

@@ -3,6 +3,7 @@
   "version": "2.5.57",
   "description": "Extending and consolidating hosts files from several well-curated sources like adaway.org, mvps.org, malwaredomainlist.com, someonewhocares.org, and potentially others. You can optionally invoke extensions to block additional sites by category.",
   "main": "",
+  "private": true,
   "scripts": {
     "test": "python3 testUpdateHostsFile.py",
     "start": "python3 makeHosts.py",