BUG-8792: allow transactions to not time out after reconnect

BUG-8792: allow transactions to not time out after reconnect

During reconnect churn, the frontend may be catching up with previous
transactions, hence we should hold off timing it out until it does.

When we arrive at a timed out transaction, we allow the access time to
be updated to connect time -- effectively saying the transaction was
touched at the time of reconnect.

Change-Id: I3930b5782579f50931b204d8579c2aee51e2bc55
Signed-off-by: Robert Varga <robert.varga@pantheon.tech>
(cherry picked from commit 55661ed801e178812f16ac990c93b51a3d68c00e)