Added clean-css as a peer dependency

Author: jackdomleo7

package-lock.json

@@ -10,7 +10,7 @@
     "build:errors-and-warnings": "sass --no-source-map src/checka11y.scss ./checka11y.css --style=compressed && sass --no-source-map ./checka11y.css ./checka11y.css --style=expanded && npx postcss checka11y.css --use autoprefixer --replace --no-map",
     "build:errors-only": "sass --no-source-map src/errors/checka11y-errors.scss ./checka11y-errors.css --style=compressed && sass --no-source-map ./checka11y-errors.css ./checka11y-errors.css --style=expanded && npx postcss checka11y-errors.css --use autoprefixer --replace --no-map",
     "build:warnings-only": "sass --no-source-map src/warnings/checka11y-warnings.scss ./checka11y-warnings.css --style=compressed && sass --no-source-map ./checka11y-warnings.css ./checka11y-warnings.css --style=expanded && npx postcss checka11y-warnings.css --use autoprefixer --replace --no-map",
-    "build:minify": "npm run build && cleancss --batch --batch-suffix '.min' checka11y.css checka11y-errors.css checka11y-warnings.css",
+    "build:minify": "npm run build && cleancss --batch --batch-suffix .min checka11y.css checka11y-errors.css checka11y-warnings.css",
     "lint:check": "stylelint \"**/*.scss\" --max-warnings=0 --ignore-path .gitignore",
     "lint:fix": "stylelint \"**/*.scss\" --max-warnings=0 --ignore-path .gitignore --fix",
     "test": "cypress run",
@@ -70,6 +70,7 @@
   ],
   "devDependencies": {
     "autoprefixer": "^10.4.0",
+    "clean-css": "^5.2.2",
     "clean-css-cli": "^5.4.2",
     "cypress": "^8.7.0",
     "git-branch-is": "^4.0.0",