databases/postgresql15-*: Upgrade to 15.0-rc1
The PostgreSQL Global Development Group announces that the first release
candidate of PostgreSQL 15 is now available for download. As a release
candidate, PostgreSQL 15 RC 1 will be mostly identical to the initial
release of PostgreSQL 15, though some more fixes may be applied prior to
the general availability of PostgreSQL 15.
To upgrade to PostgreSQL 15 RC 1 from earlier versions of PostgreSQL,
you will need to use a major version upgrade strategy, e.g. pg_upgrade
or pg_dump / pg_restore. For more information, please visit the
documentation section on upgrading.