Users: Add get_user() alias.

Add `get_user()` as an alias for `get_user_by( 'id', $user_id )`. Add `get_user()` to `user.php` so it is not a pluggable function. Bring parity with other standard `get_` functions for a more intuitive developer experience.

Props sc0ttkclark, kushang78, joedolson, peterwilsoncc.
Fixes #35124.

git-svn-id: https://develop.svn.wordpress.org/trunk@59111 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/user.php

@@ -775,6 +775,19 @@ function delete_user_option( $user_id, $option_name, $is_global = false ) {
 	return delete_user_meta( $user_id, $option_name );
 }
 
+/**
+ * Retrieves user info by user ID.
+ *
+ * @since 6.7
+ *
+ * @param int $user_id User ID.
+ *
+ * @return WP_User|false WP_User object on success, false on failure.
+ */
+function get_user( $user_id ) {
+	return get_user_by( 'id', $user_id );
+}
+
 /**
  * Retrieves list of users matching criteria.
  *