Fix HTML link helpers/form_helper.rst

Co-authored-by: kenjis <kenji.uui@gmail.com>

Author: obozdag

user_guide_src/source/helpers/form_helper.rst

@@ -117,7 +117,7 @@ The following functions are available:
             for POST/PUT/DELETE/PATCH requests, but even for GET requests, CSRF filters must be enabled for pages that display Forms.
 
             If you enable CSRF filter with `$globals <https://codeigniter4.github.io/CodeIgniter4/incoming/filters.html#globals>`, it will be active for all request types.
-            But if you enable CSRF filter with public array $methods = ['POST' => ['csrf']];, the hidden CSRF field will not be added in GET requests.
+            But if you enable CSRF filter with ``public array $methods = ['POST' => ['csrf']];``, the hidden CSRF field will not be added in GET requests.
 
     **Adding Hidden Input Fields**