Fix description in the module openy_node_activity

[anprok]

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Thank you for your contribution!

D.org issue https://www.drupal.org/node/2885223

Steps for review

• Open openY
• Login as admin
• Go to /node/add/activity
• Check Program Subcategory field description

[gundevel]

Build comment file:

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

Environment	Link
Fresh OpenY installation	http://ci.openymca.org/build1445
Upgraded(upgrade path) installation	http://upgrade.openy-dev.ffwua.com/build1445
Installation process	http://install.openy-dev.ffwua.com/build1445/install.php

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