minor symfony#12906 Update extending.rst (atailouloute)

This PR was submitted for the 4.3 branch but it was merged into the 3.4 branch instead (closes symfony#12906).

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Update extending.rst

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dd50317 Update extending.rst

Author: OskarStark

components/expression_language/extending.rst

@@ -49,7 +49,7 @@ Example::
 
 In addition to the custom function arguments, the **evaluator** is passed an
 ``arguments`` variable as its first argument, which is equal to the second
-argument of ``compile()`` (e.g. the "values" when evaluating an expression).
+argument of ``evaluate()`` (e.g. the "values" when evaluating an expression).
 
 .. _components-expression-language-provider: