minor symfony#17264 [Form] Fixing path (ThomasLandauer)

This PR was merged into the 4.4 branch.

Discussion
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[Form] Fixing path

All other code samples on this page are using `form/`

Commits
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e6bdd5d Fixing path

Author: OskarStark

form/form_themes.rst

@@ -128,7 +128,7 @@ order is important, because each theme overrides all the previous ones):
     {# apply multiple form themes but only to the form of this template #}
     {% form_theme form with [
         'foundation_5_layout.html.twig',
-        'forms/my_custom_theme.html.twig'
+        'form/my_custom_theme.html.twig'
     ] %}
 
     {# ... #}