title: Function uuid_generate_v4() does not exist postgres 11
body: <p>I am trying to use <code>node-pg-migrate</code> and run migrations to create tables in my node project.
  When I run migrations I get function uuid_generate_v4() does not exist.</p>
  
  <p>I did check in my extensions and uuid-ossp is available.</p>
  
  <pre><code>extname  | extowner | extnamespace | extrelocatable | extversion | extconfig | extcondition 
  -----------+----------+--------------+----------------+------------+-----------+--------------
   plpgsql   |       10 |           11 | f              | 1.0        |           | 
   uuid-ossp |    16384 |         2200 | t              | 1.1        |           | 
  (2 rows)
  
  </code></pre>
  
  <p>I expect my migrations to run but it fails. I am using Postgres 11 on Mac.
  Postgres installed from here - <a href="https://postgresapp.com/" rel="noreferrer">https://postgresapp.com/</a></p>