chore(deps-dev): bump gulp-autoprefixer from 6.1.0 to 7.0.0

Bumps [gulp-autoprefixer](https://github.com/sindresorhus/gulp-autoprefixer) from 6.1.0 to 7.0.0.
- [Release notes](https://github.com/sindresorhus/gulp-autoprefixer/releases)
- [Commits](sindresorhus/gulp-autoprefixer@v6.1.0...v7.0.0)

Signed-off-by: dependabot-preview[bot] <[email protected]>

Author: dependabot-preview[bot]

package-lock.json

@@ -34,7 +34,7 @@
     "cypress": "^3.4.1",
     "del": "^5.0.0",
     "gulp": "^4.0.2",
-    "gulp-autoprefixer": "^6.1.0",
+    "gulp-autoprefixer": "^7.0.0",
     "gulp-concat": "^2.6.1",
     "gulp-cssnano": "^2.1.3",
     "gulp-flatmap": "^1.0.2",