PETSc helper script needs updating for versions >= 3.20
Issue #263
new
After version 3.19 it seems PETSc have moved the location of the tar balls of releases from an old FTP server to https://web.cels.anl.gov/projects/petsc/download/release-snapshots/petsc-<VERSION>.tar.gz
Our help script ci_fetch_and_build_petsc_and_slepc.sh therefore will not work for versions after 3.19. We will need to add some logic to deal with this move or decide that we only support versions after 3.19?