fix(api): clients api docs

apps/emqx_management/src/emqx_mgmt_api_clients.erl

@@ -153,9 +153,9 @@ properties(client) ->
     {'recv_msg.qos2',   integer,
      <<"Number of PUBLISH QoS2 packets received">>},
     {'recv_msg.dropped', integer,
-     <<"Number of Dropped PUBLISH packets received">>},
+     <<"Number of dropped PUBLISH packets">>},
     {'recv_msg.dropped.expired', integer,
-     <<"Number of Dropped Expired PUBLISH packets received">>},
+     <<"Number of dropped PUBLISH packets due to expired">>},
     {recv_oct,          integer,
      <<"Number of bytes received by EMQ X Broker (the same below)">>},
     {recv_pkt,          integer,
@@ -173,13 +173,13 @@ properties(client) ->
     {'send_msg.qos2',   integer,
      <<"Number of PUBLISH QoS2 packets sent">>},
     {'send_msg.dropped', integer,
-     <<"Number of Dropped PUBLISH packets sent">>},
+     <<"Number of dropped PUBLISH packets">>},
     {'send_msg.dropped.expired', integer,
-     <<"Number of Dropped Expired PUBLISH packets sent">>},
+     <<"Number of dropped PUBLISH packets due to expired">>},
     {'send_msg.dropped.queue_full', integer,
-     <<"Number of Dropped Queue Full PUBLISH packets sent">>},
+     <<"Number of dropped PUBLISH packets due to queue full">>},
     {'send_msg.dropped.too_large', integer,
-     <<"Number of Dropped Too Large PUBLISH packets sent">>},
+     <<"Number of dropped PUBLISH packets due to packet length too large">>},
     {send_oct,          integer,
      <<"Number of bytes sent">>},
     {send_pkt,          integer,