Bug 37461: Typo in SMSSendAdditionalOptions description

Bug 37461: Typo in SMSSendAdditionalOptions description

This patch correct a typo in the SMSSendAdditionalOptions system
preference description.

To test:
1. Apply patch
2. Go to Administration > System preferences
3. Search for SMSSendAdditionalOptions
4. Read the description, make sure there are no spelling or grammar
   error

Signed-off-by: Laura_Escamilla <laura.escamilla@bywatersolutions.com>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Katrin Fischer <katrin.fischer@bsz-bw.de>