Merge branch 'ps/ci-avoid-broken-sudo-on-ubuntu'

Our CI script requires "sudo" that can be told to preserve
environment, but Ubuntu replaced with "sudo" with an implementation
that lacks the feature.  Work this around by reinstalling the
original version.

* ps/ci-avoid-broken-sudo-on-ubuntu:
  ci: fix broken jobs on Ubuntu 25.10 caused by switch to sudo-rs(1)

diff --cc ci/install-dependencies.sh
index 0d3aa496fc3a24afb8e74c131222c9681423cb23,6668c4df849350f243cf6948af11575ffbaa9909..a8dcd9b9bcd5b683871410b022cca29906fcf8fc
--- 1/ci/install-dependencies.sh
--- 2/ci/install-dependencies.sh
+++ b/ci/install-dependencies.sh
@@@ -62,9 -58,18 +62,18 @@@ ubuntu-*|i386/ubuntu-*|debian-*
                make libssl-dev libcurl4-openssl-dev libexpat-dev wget sudo default-jre \
                tcl tk gettext zlib1g-dev perl-modules liberror-perl libauthen-sasl-perl \
                libemail-valid-perl libio-pty-perl libio-socket-ssl-perl libnet-smtp-ssl-perl libdbd-sqlite3-perl libcgi-pm-perl \
 -              libsecret-1-dev libpcre2-dev meson ninja-build pkg-config \
 +              libsecret-1-dev libpcre2-dev meson ninja-build pkg-config cargo \
                ${CC_PACKAGE:-${CC:-gcc}} $PYTHON_PACKAGE
  
+       # Starting with Ubuntu 25.10, sudo can now be provided via either
+       # sudo(1) or sudo-rs(1), with the latter being the default. The problem
+       # is that it does not support `--preserve-env` though, which we rely on
+       # in our CI. We thus revert back to the C implementation.
+       if test -f /etc/alternatives/sudo
+       then
+               sudo update-alternatives --set sudo /usr/bin/sudo.ws
+       fi
+ 
        case "$distro" in
        ubuntu-*)
                mkdir --parents "$CUSTOM_PATH"