add pg_net tests

Author: olirice

nix/tests/expected/pg_net.out

@@ -0,0 +1,11 @@
+-- This is a very basic test because you can't get the value returned
+-- by a pg_net request in the same transaction that created it;
+select
+  net.http_get (
+    'https://postman-echo.com/get?foo1=bar1&foo2=bar2'
+  ) as request_id;
+ request_id 
+------------
+          1
+(1 row)
+

nix/tests/sql/pg_net.sql

@@ -0,0 +1,7 @@
+-- This is a very basic test because you can't get the value returned
+-- by a pg_net request in the same transaction that created it;
+
+select
+  net.http_get (
+    'https://postman-echo.com/get?foo1=bar1&foo2=bar2'
+  ) as request_id;