hiredis: update to version 1.2.0

hiredis: update to version 1.2.0

Announcing Hiredis v1.2.0 with with new adapters, and a great many bug
fixes.

 🚀 New Features
 - Add sdevent adapter
 - Allow specifying the keepalive interval
 - Add RedisModule adapter
 - Helper for setting TCP_USER_TIMEOUT socket option

 🐛 Bug Fixes
 - Fix a typo in b6a052f.
 - Fix wincrypt symbols conflict
 - Don't attempt to set a timeout if we are in an error state.
 - Accept -nan per the RESP3 spec recommendation.
 - Fix colliding option values
 - Ensure functionality without `_MSC_VER` definition

 🧰 Maintenance
 - Add a test for the TCP_USER_TIMEOUT option.
 - Add -Werror as a default.
 - CI: Update homebrew Redis version.
 - Fix typo in makefile.
 - Write a version file for the CMake package
 - CMakeLists.txt: respect BUILD_SHARED_LIBS
 - Cmake static or shared
 - fix typo
 - Add a test ensuring we don't clobber connection error.
 - Search for openssl on macOS

Signed-off-by: Daniel Golle <daniel@makrotopia.org>