minor symfony#9174 [DoctrineBundle] Very little typo (kevin-verschaeve)

This PR was merged into the 4.0 branch.

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[DoctrineBundle] Very little typo

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f571977 [DoctrineBundle] Very little typo

Author: javiereguiluz

reference/configuration/doctrine.rst

@@ -503,7 +503,7 @@ One of ``annotation`` (the default value), ``xml``, ``yml``, ``php`` or
 dir
 ...
 
-Absolute path to the mapping or entity files (depending on the driver.
+Absolute path to the mapping or entity files (depending on the driver).
 
 prefix
 ......