There have been recent build failures in build_renesas_ra_board. It
appears to be the case that a security update for this package was recently
issued by Ubuntu for CVE-2025-4565 and the buggy version is no longer on
package servers. However, it is still referred to by the cached apt
metadata in the GitHub runners.
Add `apt-get update` to fix this, and audit for other sites in `ci.sh`
where it might also be necessary.
Signed-off-by: Jeff Epler <jepler@gmail.com>
499bedf7aa