Fix an missing yield in the safaricom transport.
Fix an missing yield in the safaricom transport.

TouK/vumi,harrissoerja/vumi,vishwaprakashmishra/xmatrix,TouK/vumi,harrissoerja/vumi,harrissoerja/vumi,vishwaprakashmishra/xmatrix,vishwaprakashmishra/xmatrix,TouK/vumi