minor #10683 Typo fix (Geekimo)

This PR was submitted for the master branch but it was merged into the 2.8 branch instead (closes #10683).

Discussion
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Typo fix

iterator_to_array is not a method, it's a function.

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Commits
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d1035ad Typo fix

Author: javiereguiluz

components/finder.rst

@@ -53,7 +53,7 @@ the Finder instance.
 
     A Finder instance is a PHP :phpclass:`Iterator`. So, in addition to iterating over the
     Finder with ``foreach``, you can also convert it to an array with the
-    :phpfunction:`iterator_to_array` method, or get the number of items with
+    :phpfunction:`iterator_to_array` function, or get the number of items with
     :phpfunction:`iterator_count`.
 
 .. caution::