[mod] Shuffle httpx's default ciphers of a SSL context randomly.

From the analyse of @9Ninety [1] we know that DDG (and may be other engines / I
have startpage in mind) does some kind of TLS fingerprint to block bots.

This patch shuffles the default ciphers from httpx to avoid a cipher profile
that is known to httpx (and blocked by DDG).

[1] https://github.com/searxng/searxng/issues/2246#issuecomment-1467895556

----

From `What Is TLS Fingerprint and How to Bypass It`_

> When implementing TLS fingerprinting, servers can't operate based on a
> locked-in whitelist database of fingerprints.  New fingerprints appear
> when web clients or TLS libraries release new versions. So, they have to
> live off a blocklist database instead.
> ...
> It's safe to leave the first three as is but shuffle the remaining ciphers
> and you can bypass the TLS fingerprint check.

.. _What Is TLS Fingerprint and How to Bypass It:
   https://www.zenrows.com/blog/what-is-tls-fingerprint#how-to-bypass-tls-fingerprinting



Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>
Closes: https://github.com/searxng/searxng/issues/2246