Use named boolean parameters for pg_get_*_ddl option arguments

Use named boolean parameters for pg_get_*_ddl option arguments

Replace the VARIADIC text[] alternating key/value option interface with
typed named boolean parameters for pg_get_role_ddl(), pg_get_tablespace_ddl(),
and pg_get_database_ddl(), as added by commit 4881981f920 and friends.
The new signatures are:

  pg_get_role_ddl(role regrole,
                  pretty boolean DEFAULT false,
                  memberships boolean DEFAULT true)

  pg_get_tablespace_ddl(tablespace oid/name,
                        pretty boolean DEFAULT false,
                        owner boolean DEFAULT true)

  pg_get_database_ddl(db regdatabase,
                      pretty boolean DEFAULT false,
                      owner boolean DEFAULT true,
                      tablespace boolean DEFAULT true)

This provides type safety at the SQL level, allows named-argument calling
syntax (pretty => true), removes the runtime string-parsing machinery
(DdlOption, parse_ddl_options) in favour of direct PG_GETARG_BOOL() calls,
and allows the functions to be marked STRICT.

While we're here, I added an extra TAP test for pg_get_database(owner =>
false, ...)

Catalog version bumped.

Author: Jelte Fennema-Nio <postgres@jeltef.nl>
Discussion: https://postgr.es/m/DHM6C7SLS4BN.1WW9Z4PRPN0VJ@jeltef.nl
(and on Discord)