build(deps): bump webpack-sources from 2.2.0 to 3.2.0 (#734)

Bumps [webpack-sources](https://github.com/webpack/webpack-sources) from 2.2.0 to 3.2.0.
- [Release notes](https://github.com/webpack/webpack-sources/releases)
- [Commits](webpack/webpack-sources@v2.2.0...v3.2.0)

---
updated-dependencies:
- dependency-name: webpack-sources
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

packages/purgecss-webpack-plugin/package.json

@@ -38,7 +38,7 @@
   "dependencies": {
     "purgecss": "^4.0.3",
     "webpack": "^5.4.0",
-    "webpack-sources": "^2.0.0"
+    "webpack-sources": "^3.2.0"
   },
   "bugs": {
     "url": "https://github.com/FullHuman/purgecss/issues"