Change directories to os-service-types during update

The update script framework calls the update function with an argument
of the directory of the project we're trying to update. The update
script needs to pushd into it before curling the new content.

Change-Id: Ic569aee5716ca32e755adda02f149359b532c4fc

jenkins/scripts/propose_update.sh

@@ -79,7 +79,9 @@ elif [ "$OWN_PROJECT" == "os-service-types" ] ; then
     TOPIC="openstack/os-service-types/sync-service-types-authority"
     PROJECTS="openstack/os-service-types"
     function update {
+        pushd $1
         curl https://service-types.openstack.org/service-types.json > os_service_types/data/service-types.json
+        popd
     }
 else
     echo "Unknown project $1" >2