Abort the mock time sync client connection instead of closing
Abort the mock time sync client connection instead of closing

Simply closing the connection was leaving a TCP socket retrying
transmissions in a failed case when running with plaid, and that in
turn was being flagged as a resource leak.

Change-Id: Ic25ec1fe16381e74e77c83dc66a35ccc4e519775

openweave/openweave-core,openweave/openweave-core,openweave/openweave-core,openweave/openweave-core,openweave/openweave-core,openweave/openweave-core