restore removed exec

exec is required to correctly handle signals by hivemind
python code, without exec (when there is no additional processes between
hivemind and linux)  signals are not delivered to hivemind

exec was removed wit commit: 1751bc56

docker/docker_entrypoint.sh

@@ -66,10 +66,10 @@ run_hive() {
   source /home/hivemind/.hivemind-venv/bin/activate
   if [[ -n "$LOG_PATH" ]]; then
     log "run_hive" "Starting Hivemind with log $LOG_PATH"
-    hive "${HIVEMIND_ARGS[@]}" --database-url="${db_url}" > >( tee -i "$LOG_PATH" ) 2>&1
+    exec hive "${HIVEMIND_ARGS[@]}" --database-url="${db_url}" > >( tee -i "$LOG_PATH" ) 2>&1
   else
     log "run_hive" "Starting Hivemind..."
-    hive "${HIVEMIND_ARGS[@]}" --database-url="${db_url}"
+    exec hive "${HIVEMIND_ARGS[@]}" --database-url="${db_url}"
   fi
 }