Bump gulp-autoprefixer from 7.0.1 to 8.0.0 (#283)

Bumps [gulp-autoprefixer](https://github.com/sindresorhus/gulp-autoprefixer) from 7.0.1 to 8.0.0.
- [Release notes](https://github.com/sindresorhus/gulp-autoprefixer/releases)
- [Commits](sindresorhus/gulp-autoprefixer@v7.0.1...v8.0.0)

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

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

Author: dependabot-preview[bot]

package.json

@@ -48,7 +48,7 @@
     "eslint-plugin-jsx-a11y": "^6.0.2",
     "eslint-plugin-react": "^7.10.0",
     "gulp": "^4.0.0",
-    "gulp-autoprefixer": "^7.0.0",
+    "gulp-autoprefixer": "^8.0.0",
     "gulp-clean-css": "^4.0.0",
     "gulp-eslint": "^6.0.0",
     "gulp-exec": "^5.0.0",