Bump lodash from 4.17.21 to 4.17.23 in /util/gradientgen

Bumps [lodash](https://github.com/lodash/lodash) from 4.17.21 to 4.17.23.
- [Release notes](https://github.com/lodash/lodash/releases)
- [Commits](lodash/lodash@4.17.21...4.17.23)

---
updated-dependencies:
- dependency-name: lodash
  dependency-version: 4.17.23
  dependency-type: direct:production
...

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Author: dependabot[bot]

util/gradientgen/package-lock.json

@@ -4,7 +4,7 @@
   "description": "Generates gradient presets for QGradient",
   "main": "gradientgen.js",
   "dependencies": {
-    "lodash": "^4.17.21",
+    "lodash": "^4.17.23",
     "mathjs": "^7.5.1",
     "parse-color": "^1.0.0",
     "postcss-minify-gradients": "^6.0.0",