docs: mention browserslist may be in separate file [ci skip]

Author: yyx990803

docs/guide/browser-compatibility.md

@@ -2,7 +2,7 @@
 
 ## browserslist
 
-You will notice a `browserslist` field in `package.json` specifying a range of browsers the project is targeting. This value will be used by [@babel/preset-env][babel-preset-env] and [autoprefixer][autoprefixer] to automatically determine the JavaScript features that need to be transpiled and the CSS vendor prefixes needed.
+You will notice a `browserslist` field in `package.json` (or a separate `.browserslistrc` file) specifying a range of browsers the project is targeting. This value will be used by [@babel/preset-env][babel-preset-env] and [autoprefixer][autoprefixer] to automatically determine the JavaScript features that need to be transpiled and the CSS vendor prefixes needed.
 
 See [here][browserslist] for how to specify browser ranges.