Update service_create.md
Update service_create.md

Typo in word propagation.

Signed-off-by: Jose Escobar <20a8cfc88d8a6e367d3e2cb8c1fd71c43d020f47@JE-MBP15-2017.local>

cpuguy83/cli,docker/cli,docker/cli,thaJeztah/cli,cpuguy83/cli,thaJeztah/cli