Fix description in field_sidebar_content.yml for class

[Sanchiz]

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[gundevel]

Build comment file:

===============

Environment	Link
Fresh OpenY installation	http://ci.openymca.org/build1505
Upgraded(upgrade path) installation	http://upgrade.openy-dev.ffwua.com/build1505
Installation process	http://install.openy-dev.ffwua.com/build1505/install.php

---

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[gundevel]

Behat test results file URL: http://ci.openymca.org/build1505/profiles/contrib/openy/build/reports/behat