Reapply "Add hpr_timestamp_ms for gwmp protocol (#313)" (#317)

This reverts commit 212c00d.

Author: macpie

src/protocols/gwmp/hpr_gwmp_worker.erl

@@ -250,7 +250,8 @@ packet_up_to_push_data(Up, Timestamp, GatewayLocation) ->
         network => <<"helium_iot">>,
         gateway_id => B58,
         gateway_name => Name,
-        regi => hpr_packet_up:region(Up)
+        regi => hpr_packet_up:region(Up),
+        hpr_timestamp_ms => Timestamp
     },
     %% NOTE: everything in meta needs to be string -> string.
     Meta =

test/hpr_protocol_gwmp_SUITE.erl

@@ -801,7 +801,8 @@ verify_push_data(PacketUp, PushDataBinary) ->
                         ),
                         <<"regi">> => erlang:atom_to_binary(
                             hpr_packet_up:region(PacketUp)
-                        )
+                        ),
+                        <<"hpr_timestamp_ms">> => fun erlang:is_integer/1
                     }
                 }
             ]
@@ -848,7 +849,8 @@ verify_push_data_with_location(PacketUp, PushDataBinary, IndexString) ->
                         ),
                         <<"gateway_h3index">> => erlang:list_to_binary(IndexString),
                         <<"gateway_lat">> => hpr_utils:format_coord(ExpectedLat),
-                        <<"gateway_long">> => hpr_utils:format_coord(ExpectedLong)
+                        <<"gateway_long">> => hpr_utils:format_coord(ExpectedLong),
+                        <<"hpr_timestamp_ms">> => fun erlang:is_integer/1
                     }
                 }
             ]