docs: add npm version script

Author: raveclassic

package.json

@@ -11,7 +11,8 @@
     "prettier": "prettier --list-different \"./src/**/*.ts\"",
     "prettier:fix": "prettier --write \"./src/**/*.ts\"",
     "prepublishOnly": "npm run test && npm run build",
-    "changelog": "conventional-changelog -p angular -i CHANGELOG.md -s -r 0"
+    "changelog": "conventional-changelog -p angular -i CHANGELOG.md -s -r 0",
+    "version": "npm run changelog && git add CHANGELOG.md"
   },
   "author": "devexperts",
   "license": "MPL-2.0",