Remove unnecessary duplicate npm test when versioning

Project uses release-it to do its releases, which handles versioning,
and already runs npm test. So no need to have it in preversion script.

Author: markcellus

package.json

@@ -48,7 +48,6 @@
     "test": "npm run test:ts && eslint 'src/**/*' && npm run prettier",
     "test:ts": "karma start test/karma.conf.cjs",
     "prettier": "prettier --check 'src/**/*'",
-    "preversion": "npm test",
     "banner": "banner-cli dist/index.js",
     "build": "tsc"
   },