Add memory usage tests

test/fixtures/privileges.sql

@@ -61,6 +61,7 @@ GRANT ALL ON TABLE
     , descendant
     , being_part
     , part
+    , leak
 TO postgrest_test_anonymous;
 
 GRANT INSERT ON TABLE insertonly TO postgrest_test_anonymous;
@@ -69,6 +70,7 @@ GRANT USAGE ON SEQUENCE
       auto_incrementing_pk_id_seq
     , items_id_seq
     , callcounter_count
+    , leak_id_seq
 TO postgrest_test_anonymous;
 
 -- Privileges for non anonymous users

test/fixtures/schema.sql

@@ -1345,3 +1345,10 @@ $$ language sql;
 create or replace function test.overloaded(a text, b text, c text) returns text as $$
   select a || b || c
 $$ language sql;
+
+create table test.leak(
+  id serial primary key,
+  blob bytea
+);
+
+CREATE FUNCTION test.leak(blob bytea) RETURNS void AS $$ BEGIN END; $$ LANGUAGE plpgsql;