[C++][CI] LLVM 13 cannot be used on macOS GHA builds

[asfimport]

See
https://github.com/apache/arrow/pull/11372/checks?check_run_id=3859972940
https://github.com/apache/arrow/pull/11372/checks?check_run_id=3859973472
https://github.com/apache/arrow/pull/11372/checks?check_run_id=3859973399

Reporter: Antoine Pitrou / @pitrou
Assignee: Kouhei Sutou / @kou

PRs and other links:

• GitHub Pull Request #11379

_{Note: This issue was originally created as ARROW-14283. Please see the migration documentation for further details.}

[asfimport]

Kouhei Sutou / @kou:
This is a workaround.

ARROW-14265 is a real fix.

[asfimport]

Kouhei Sutou / @kou:
Issue resolved by pull request 11379
#11379