amqp10_dest_validation/2: tweak wording of a long comment

Author: michaelklishin

deps/rabbitmq_shovel/src/rabbit_shovel_parameters.erl

@@ -165,10 +165,10 @@ amqp10_dest_validation(_Def, User) ->
      {<<"dest-address">>, fun rabbit_parameter_validation:binary/2, mandatory},
      {<<"dest-add-forward-headers">>, fun rabbit_parameter_validation:boolean/2, optional},
      {<<"dest-add-timestamp-header">>, fun rabbit_parameter_validation:boolean/2, optional},
-     %% The bare message should be inmutable in the AMQP network.
+     %% The bare message should be immutable in the AMQP network.
      %% Before RabbitMQ 4.2, we allowed to set application properties, message
      %% annotations and any property. This is wrong.
-     %% From 4.2, the only message modification allowed is the optional
+     %% Starting with 4.2, the only message modification allowed is the optional
      %% addition of forward headers and shovelled timestamp inside message
      %% annotations.
      %% To avoid breaking existing deployments, the following configuration