docs(config): fix typo by removing extraneous 'which' (#2670)

Author: doersino

src/content/configuration/resolve.md

@@ -389,7 +389,7 @@ T> Note that you can use alias here and other features familiar from resolve. Fo
 
 `array`
 
-The extensions/suffixes which that are used when resolving loaders. Since version two, we [strongly recommend](/migrate/3/#automatic-loader-module-name-extension-removed) using the full name, e.g. `example-loader`, as much as possible for clarity. However, if you really wanted to exclude the `-loader` bit, i.e. just use `example`, you can use this option to do so:
+The extensions/suffixes that are used when resolving loaders. Since version two, we [strongly recommend](/migrate/3/#automatic-loader-module-name-extension-removed) using the full name, e.g. `example-loader`, as much as possible for clarity. However, if you really wanted to exclude the `-loader` bit, i.e. just use `example`, you can use this option to do so:
 
 ```js
 module.exports = {