chore(jwt authn): improve tests, add pool_size to schema

apps/emqx_authn/src/simple_authn/emqx_authn_jwt.erl

@@ -72,6 +72,7 @@ fields('jwks') ->
     [
         {use_jwks, sc(hoconsc:enum([true]), #{required => true, desc => ?DESC(use_jwks)})},
         {endpoint, fun endpoint/1},
+        {pool_size, fun emqx_connector_schema_lib:pool_size/1},
         {refresh_interval, fun refresh_interval/1},
         {ssl, #{
             type => hoconsc:union([

apps/emqx_authn/test/emqx_authn_jwt_SUITE.erl

@@ -61,7 +61,7 @@ t_jwt_authenticator_hmac_based(_) ->
         algorithm => 'hmac-based',
         secret => Secret,
         secret_base64_encoded => false,
-        verify_claims => []
+        verify_claims => [{<<"username">>, <<"${username}">>}]
     },
     {ok, State} = emqx_authn_jwt:create(?AUTHN_ID, Config),