docs: variable naming adjustments (codeigniter4#9324)

* Update 006.php

* Update 008.php

* Update 046.php

Author: andifahruddinakas

user_guide_src/source/models/model/006.php

@@ -1,3 +1,3 @@
 <?php
 
-$user = $userModel->find($user_id);
+$user = $userModel->find($userId);

user_guide_src/source/models/model/008.php

@@ -1,3 +1,3 @@
 <?php
 
-$user = $userModel->findColumn($column_name);
+$user = $userModel->findColumn($columnName);

user_guide_src/source/models/model/046.php

@@ -1,3 +1,3 @@
 <?php
 
-$user_name = $userModel->escape($name);
+$userName = $userModel->escape($name);