Updates default value for replication_sync_timeout

Changes default value in the description from 300 to 0
Fixes #5183

Author: AArdeev

doc/reference/configuration/cfg_replication.rst

@@ -394,14 +394,14 @@
 
     |
     | Type: float
-    | Default: 300
+    | Default: 0
     | Environment variable: TT_REPLICATION_SYNC_TIMEOUT
     | Dynamic: yes
 
     .. NOTE::
 
-        The default ``replication_sync_timeout`` value is going to be changed in future versions from ``300`` to ``0``.
-        You can learn the reasoning behind this decision from the :ref:`Default value for replication_sync_timeout <compat-option-replication-timeout>` topic, which also describes how to try the new behavior in the current version.
+        The default ``replication_sync_timeout`` value can be changed to 300 by using the ``compat`` module.
+        More information on how to change the default value see in :ref:`Default value for replication_sync_timeout <compat-option-replication-timeout>`.
 
 .. _cfg_replication-replication_timeout:
 

doc/reference/reference_lua/box_cfg.rst

@@ -76,7 +76,7 @@ default settings to all the parameters:
       replication_connect_timeout  = 30
       replication_skip_conflict    = false
       replication_sync_lag         = 10
-      replication_sync_timeout     = 300
+      replication_sync_timeout     = 0
       replication_timeout          = 1
       slab_alloc_factor            = 1.05
       snap_io_rate_limit           = nil