Update ESLint related dependencies (major) (#18907)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
Co-authored-by: fisker <lionkay@gmail.com>

src/language-css/parse/parse-value.js

@@ -177,7 +177,7 @@ function parseValue(value, options) {
     return { type: "value-unknown", value };
   }
 
-  let result = null;
+  let result;
 
   try {
     result = new PostcssValuesParser(value, { loose: true }).parse();