minor #4455 Simplify enum usage in docs (ruudk)

This PR was squashed before being merged into the 3.x branch.

Discussion
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Simplify enum usage in docs

There is no need to use `()`.

Commits
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7556fe1c6f Simplify enum usage in docs

doc/functions/enum.rst

@@ -13,7 +13,7 @@
     {{ enum('App\\MyEnum').SomeCase.value }}
 
     {# get all cases of an enum #}
-    {% enum('App\\MyEnum').cases() %}
+    {% enum('App\\MyEnum').cases %}
 
     {# call any methods of the enum class #}
     {% enum('App\\MyEnum').someMethod() %}