Update Dockerfile to set debug logFile to /var/log/hsflowd.log (signal process...

Update Dockerfile to set debug logFile to /var/log/hsflowd.log (signal process with SIGUSR2 to increase debug level)

agent/Dockerfile

@@ -29,4 +29,4 @@ COPY --from=gobuilder /usr/sbin/hsflowd_containerd /usr/sbin/hsflowd_containerd
 COPY --from=builder /usr/sbin/hsflowd /usr/sbin/hsflowd
 COPY --from=builder /etc/hsflowd.conf /etc/hsflowd.conf
 COPY --from=builder /etc/hsflowd/modules/* /etc/hsflowd/modules/
-CMD /usr/sbin/hsflowd -m `uuidgen` -d
+CMD /usr/sbin/hsflowd -m `uuidgen` -d -D /var/log/hsflowd.log