• steps to reproduce:
  Try to build a package using _libremakepkg, which has _{aom-3.1.1-x86_64} as a dependency, either directly or indirectly. This is happening to me when trying to build the latest version of _minitube (3.9).

• expected result:
  It should build successfully, even after switching to a different default mirror.

• actual result:
  Instead, _libremakepkg prints the following error:

 |   > 
 |   > Total Download Size:    49.39 MiB
 |   > Total Installed Size:  792.63 MiB
 |   > 
 |   > :: Proceed with installation? [Y/n] 
 |   > :: Retrieving packages...
 |   >  aom-3.1.1-1-x86_64 downloading...
 |   > error: failed retrieving file 'aom-3.1.1-1-x86_64.pkg.tar.zst' from mirror.fsf.org : The requested URL returned error: 404
 |   > warning: failed to retrieve some files
 |   > error: failed to commit transaction (failed to retrieve some files)
 |   > Errors occurred, no packages were upgraded.
==> ERROR: Failure(s) in pre_build: clean_chroot