Revert "Merge pull request #13544 from rabbitmq/mergify/bp/v4.0.x/pr-13543"

This reverts commit 5107667, reversing
changes made to 2154336.

We'll keep this change 4.1.0-specific because it can
affect a very small percentage of clients that override
frame_max to a value lower than 8192 bytes.

Author: michaelklishin

deps/rabbit_common/include/rabbit_framing.hrl

@@ -11,7 +11,7 @@
 -define(FRAME_HEADER, 2).
 -define(FRAME_BODY, 3).
 -define(FRAME_HEARTBEAT, 8).
--define(FRAME_MIN_SIZE, 8192).
+-define(FRAME_MIN_SIZE, 4096).
 -define(FRAME_END, 206).
 -define(REPLY_SUCCESS, 200).
 -define(CONTENT_TOO_LARGE, 311).