apt-check standard output (without --human-readable) does not count or distinguish ESM packages

[Mark Cunningham]

The standard output from apt-check only reports "uprades;security_updates" when not using the --human-readable flag.

The request here is to update this standard output to either include ESM updates in the count shown "security_updates+esm_infra_updates" or to otherwise separate out "esm_infra_updates" and potentially "esm_apps_updates" into separate values in the standard output.

This is somewhat related to the previously resolved bug 1926208 (https://bugs.launchpad.net/ubuntu/+source/update-notifier/+bug/1926208), where the --human-readable output was updated to make this distinction between security/ESM-infra/ESM-apps.

Here is what is currently in the script:

---
    # print the number of upgrades
    if options and options.show_package_names:
        write_package_names(sys.stderr, cache, depcache)
    elif options and options.readable_output:
        write_human_readable_summary(sys.stdout, upgrades, security_updates,
                                     esm_infra_updates, esm_apps_updates,
                                     have_esm_infra, have_esm_apps,
                                     disabled_esm_infra_updates,
                                     disabled_esm_apps_updates)
    else:
        # print the number of regular upgrades and the number of
        # security upgrades
        sys.stderr.write("%s;%s" % (upgrades, security_updates))

    # return the number of upgrades (if its used as a module)
    return(upgrades, security_updates)
---

The request here is for any of the following to be used in /usr/lib/update-notifier/apt-check for output not using the --human-readable flag.

---
sys.stderr.write("%s;%s;%s;%s" % (upgrades, security_updates, esm_infra_updates, esm_apps_updates))

---
sys.stderr.write("%s;%s;%s" % (upgrades, security_updates, esm_infra_updates+esm_apps_updates))

---
sys.stderr.write("%s;%s" % (upgrades, security_updates+esm_infra_updates+esm_apps_updates))

---

This should likely also be updated for the return value in the script as well, so that those values match whatever output is decided for the above request.