Test pull requests in Cirrus CI.
Test pull requests in Cirrus CI.

Both FreedBSD and MacOS use clang as their default compiler and clang catches some errors that gcc does not. Specifically, wide integers being assigned to short integers resulting in possible truncations.

pgbackrest/pgbackrest,pgmasters/backrest,pgbackrest/pgbackrest,pgmasters/backrest,pgbackrest/pgbackrest