Bump haproxy version to 2.8.14

[CFN-CI]

Automatic bump from version 2.8.13 to version 2.8.14, downloaded from https://www.haproxy.org/download/2.8/src/haproxy-2.8.14.tar.gz.

After merge, consider releasing a new version of haproxy-boshrelease.

[peanball]

release note: https://www.mail-archive.com/haproxy@formilux.org/msg45570.html

Somewhat relevant points:

• Most of remaining issues with the queues management were fixed. The
  dequeuing process is now called when a stream is closed. This should
  unsure no stream remains infinitely blocked in the queue and prevent any
  infinite loop in some extreme cases. It was also possible to exceed the
  configured maxconn when a server was brought back up. It appears that
  only the proxy queue was evaluated at this stage while the server queue
  must also be processed. Note that the issue it not totally fixed in
  3.0. We can occasionally see a few more connections than maxconn, but
  the max that have been observed is 4 more connections, we no longer get
  multiple times maxconn. This was improved in the 3.2 to strictly respect
  the maxconn value.
• In H1, it was possible to have unusable client connections waiting for
  the client timeout while they should be closed. This happened when a
  connection error was immediately encountered after the connection
  establishment, in same time of the connection closure. It was not a leak
  because connections were finally closed but it was a waste of
  ressources, especially with a high client timeout.
• The H1 multiplexer was only able to handle timeouts if the client or
  server timeouts were defined, depending on the side. So, it was possible
  to ignore client-fin/server-fin and http-keep-alive/http-request
  timeouts.