add to metadata test case with k/v property

apps/opentelemetry/test/opentelemetry_SUITE.erl

@@ -218,7 +218,7 @@ propagation(Config) ->
     otel_baggage:set(<<"key-1">>, <<"value=1">>, []),
     %% TODO: should the whole baggage entry be dropped if metadata is bad?
     %% drop bad metadata (the `1').
-    otel_baggage:set(<<"key-2">>, <<"value-2">>, [<<"metadata">>, 1]),
+    otel_baggage:set(<<"key-2">>, <<"value-2">>, [<<"metadata">>, 1, {<<"md-k-1">>, <<"md-v-1">>}]),
     %% drop baggage with bad value
     otel_baggage:set(<<"key-3">>, value3),
 
@@ -227,14 +227,14 @@ propagation(Config) ->
     EncodedTraceId = io_lib:format("~32.16.0b", [TraceId]),
     EncodedSpanId = io_lib:format("~16.16.0b", [SpanId]),
 
-    ?assertListsEqual([{<<"baggage">>, <<"key-2=value-2;metadata,key-1=value%3D1">>},
+    ?assertListsEqual([{<<"baggage">>, <<"key-2=value-2;metadata;md-k-1=md-v-1,key-1=value%3D1">>},
                        {<<"existing-header">>, <<"I exist">>} |
                        trace_context(Propagator, EncodedTraceId, EncodedSpanId)], Headers),
 
     ?end_span(SpanCtx),
 
     ?assertEqual(#{<<"key-1">> => {<<"value=1">>, []},
-                   <<"key-2">> => {<<"value-2">>, [<<"metadata">>]}}, otel_baggage:get_all()),
+                   <<"key-2">> => {<<"value-2">>, [<<"metadata">>, {<<"md-k-1">>, <<"md-v-1">>}]}}, otel_baggage:get_all()),
 
     %% ?end_span doesn't remove the span from the context
     ?assertEqual(SpanCtx, ?current_span_ctx),
@@ -250,7 +250,7 @@ propagation(Config) ->
     otel_propagator:text_map_extract(BinaryHeaders),
 
     ?assertEqual(#{<<"key-1">> => {<<"value=1">>, []},
-                   <<"key-2">> => {<<"value-2">>, [<<"metadata">>]}}, otel_baggage:get_all()),
+                   <<"key-2">> => {<<"value-2">>, [<<"metadata">>, {<<"md-k-1">>, <<"md-v-1">>}]}}, otel_baggage:get_all()),
 
     %% extracted remote spans are set to the active span
     %% but with `is_recording' false