Make both net tables UNLOGGED

Their contents shouldn't survive a crash, and UNLOGGED makes the
INSERTs/DELETEs faster and consume less CPU.

Author: steve-chavez

sql/pg_net--0.4--0.5.sql

@@ -4,3 +4,5 @@ alter table net._http_response drop constraint _http_response_pkey;
 drop trigger ensure_worker_is_up on net.http_request_queue;
 alter function net._check_worker_is_up() rename to check_worker_is_up;
 drop index net._http_response_created_idx;
+alter table net.http_request_queue set unlogged;
+alter table net._http_response set unlogged;

sql/pg_net.sql

@@ -8,7 +8,7 @@ check (
 
 -- Store pending requests. The background worker reads from here
 -- API: Private
-create table net.http_request_queue(
+create unlogged table net.http_request_queue(
     id bigserial,
     method net.http_method not null,
     url text not null,
@@ -31,7 +31,7 @@ $$ language plpgsql;
 
 -- Associates a response with a request
 -- API: Private
-create table net._http_response(
+create unlogged table net._http_response(
     id bigint,
     status_code integer,
     content_type text,