Updated ARM instance size for DS14 size.
Updated ARM instance size for DS14 size.

iamshital/azure-linux-automation,konkasoftci/azure-linux-automation,konkasoftci/azure-linux-automation,iamshital/azure-linux-automation,v-sirebb/azure-linux-automation,v-sirebb/azure-linux-automation,iamshital/azure-linux-automation,konkasoftci/azure-linux-automation,v-sirebb/azure-linux-automation