minor #3817 Update translation.rst (richardpi)

This PR was submitted for the 2.4 branch but it was merged into the 2.3 branch instead (closes #3817).

Discussion
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Update translation.rst

typo: "bahavior" -> "behavior"

Commits
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fac4e33 Update translation.rst

book/translation.rst

@@ -654,7 +654,7 @@ Translating Database Content
 ----------------------------
 
 The translation of database content should be handled by Doctrine through
-the `Translatable Extension`_ or the `Translatable Bahavior`_ (PHP 5.4+).
+the `Translatable Extension`_ or the `Translatable Behavior`_ (PHP 5.4+).
 For more information, see the documentation for thes libraries.
 
 Summary
@@ -680,4 +680,4 @@ steps:
 .. _`ISO 3166-1 alpha-2`: http://en.wikipedia.org/wiki/ISO_3166-1#Current_codes
 .. _`ISO 639-1`: http://en.wikipedia.org/wiki/List_of_ISO_639-1_codes
 .. _`Translatable Extension`: https://github.com/l3pp4rd/DoctrineExtensions
-.. _`Translatable Bahavior`: https://github.com/KnpLabs/DoctrineBehaviors
+.. _`Translatable Behavior`: https://github.com/KnpLabs/DoctrineBehaviors