Please Add Postgres Extenstions (postgresql-contrib)

The provided postgres images do not contain the postgresql-contrib.rpm which provides various postgres extensions, such as pg_trgm and btree_gist.

postgres=# create extension pg_trgm;
ERROR:  could not open extension control file "/usr/pgsql-12/share/extension/pg_trgm.control": No such file or directory
postgres=# create extension btree_gist;
ERROR:  could not open extension control file "/usr/pgsql-12/share/extension/btree_gist.control": No such file or directory
postgres=# 

Please include this library with the standard postgres image, as these extensions are common requirements for services such as gitlab: https://docs.gitlab.com/charts/advanced/external-db/#external-database-requirements