Update static-folder.md (#17753)

Sentence structure/typo fix.

docs/docs/static-folder.md

@@ -32,7 +32,7 @@ render() {
 
 Keep in mind the downsides of this approach:
 
-- None of the files in `static` folder be post-processed or minified.
+- None of the files in the `static` folder will be post-processed or minified.
 - Missing files will not be called at compilation time, and will cause 404 errors for your users.
 - Result filenames won’t include content hashes so you’ll need to add query arguments or rename them every time they change.