doc: update options.filter description for fs.cp

PR-URL: #49289
Fixes: #49092
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: LiviaMedeiros <livia@cirno.name>

doc/api/fs.md

@@ -991,7 +991,8 @@ changes:
   * `errorOnExist` {boolean} when `force` is `false`, and the destination
     exists, throw an error. **Default:** `false`.
   * `filter` {Function} Function to filter copied files/directories. Return
-    `true` to copy the item, `false` to ignore it. Can also return a `Promise`
+    `true` to copy the item, `false` to ignore it. When ignoring a directory,
+    all of its contents will be skipped as well. Can also return a `Promise`
     that resolves to `true` or `false` **Default:** `undefined`.
     * `src` {string} source path to copy.
     * `dest` {string} destination path to copy to.
@@ -2322,7 +2323,8 @@ changes:
   * `errorOnExist` {boolean} when `force` is `false`, and the destination
     exists, throw an error. **Default:** `false`.
   * `filter` {Function} Function to filter copied files/directories. Return
-    `true` to copy the item, `false` to ignore it. Can also return a `Promise`
+    `true` to copy the item, `false` to ignore it. When ignoring a directory,
+    all of its contents will be skipped as well. Can also return a `Promise`
     that resolves to `true` or `false` **Default:** `undefined`.
     * `src` {string} source path to copy.
     * `dest` {string} destination path to copy to.
@@ -5190,7 +5192,8 @@ changes:
   * `errorOnExist` {boolean} when `force` is `false`, and the destination
     exists, throw an error. **Default:** `false`.
   * `filter` {Function} Function to filter copied files/directories. Return
-    `true` to copy the item, `false` to ignore it. **Default:** `undefined`
+    `true` to copy the item, `false` to ignore it. When ignoring a directory,
+    all of its contents will be skipped as well. **Default:** `undefined`
     * `src` {string} source path to copy.
     * `dest` {string} destination path to copy to.
     * Returns: {boolean}