fix: fix system acl column type to support \l command

[yezizp2012]

I hereby agree to the terms of the RisingWave Labs, Inc. Contributor License Agreement.

What's changed and what's your intention?

As title, after this PR \l command will be available in risingwave.
FYI, the command will be translated to the following query:

SELECT
  d.datname                                               AS "Name",
  pg_catalog.pg_get_userbyid (d.datdba)                   AS "Owner",
  pg_catalog.pg_encoding_to_char (d.encoding)             AS "Encoding",
  d.datcollate                                            AS "Collate",
  d.datctype                                              AS "Ctype",
  pg_catalog.array_to_string (d.datacl, E'\n') AS "Access privileges"
FROM
  pg_catalog.pg_database AS d
ORDER BY
  1

Checklist

• I have written necessary rustdoc comments
• I have added necessary unit tests and integration tests
• I have added test labels as necessary. See details.
• I have added fuzzing tests or opened an issue to track them. (Optional, recommended for new SQL features Sqlsmith: Sql feature generation #7934).
• My PR contains breaking changes. (If it deprecates some features, please create a tracking issue to remove them in the future).
• All checks passed in ./risedev check (or alias, ./risedev c)
• My PR changes performance-critical code. (Please run macro/micro-benchmarks and show the results.)

• My PR contains critical fixes that are necessary to be merged into the latest release. (Please check out the details)

Documentation

• My PR needs documentation updates. (Please use the Release note section below to summarize the impact on users)

Release note

If this PR includes changes that directly affect users or other significant modifications relevant to the community, kindly draft a release note to provide a concise summary of these changes. Please prioritize highlighting the impact these changes will have on users.

support \l command.

[fuyufjh]

Please add an SLT for the query.

SELECT
  d.datname                                               AS "Name",
  pg_catalog.pg_get_userbyid (d.datdba)                   AS "Owner",
  pg_catalog.pg_encoding_to_char (d.encoding)             AS "Encoding",
  d.datcollate                                            AS "Collate",
  d.datctype                                              AS "Ctype",
  pg_catalog.array_to_string (d.datacl, E'\n') AS "Access privileges"
FROM
  pg_catalog.pg_database AS d
ORDER BY
  1

The rest LGTM!

[yezizp2012]

Please add an SLT for the query.

SELECT
  d.datname                                               AS "Name",
  pg_catalog.pg_get_userbyid (d.datdba)                   AS "Owner",
  pg_catalog.pg_encoding_to_char (d.encoding)             AS "Encoding",
  d.datcollate                                            AS "Collate",
  d.datctype                                              AS "Ctype",
  pg_catalog.array_to_string (d.datacl, E'\n') AS "Access privileges"
FROM
  pg_catalog.pg_database AS d
ORDER BY
  1

The rest LGTM!

It's kind of flaky because sqllogictest dynamically creates databases, resulting in unpredictable query results, especially when running in parallel mode. Let me change this query a little bit and add an SLT.