Fix unreadable output in upgrade log

This commit resolves an issue where unwanted escape sequences (e.g.,
ANSI codes) appear in the output of certain commands like `dnf` during
upgrades.

The issue arises because, starting with version 242, `systemd-nspawn`
introduced new pseudo-TTY capabilities (see the `Input/Output Options`
section in `systemd-nspawn(1)`). As a result, commands run within
container may include these escape sequences.

To address this, pseudo-TTY support is explicitly disabled in
`systemd-nspawn` for upgrades on RHEL9 and later.

JIRA: RHEL-69829

repos/system_upgrade/common/libraries/mounting.py

@@ -5,7 +5,7 @@
 from collections import namedtuple
 
 from leapp.libraries.common.config import get_all_envs
-from leapp.libraries.common.config.version import get_source_major_version
+from leapp.libraries.common.config.version import get_source_major_version, matches_source_version
 from leapp.libraries.stdlib import api, CalledProcessError, run
 
 # Using ALWAYS_BIND will crash the upgrade process if the file does not exist.
@@ -88,6 +88,9 @@ def make_command(self, cmd):
                 # in such a case, just add line into the previous solution..
                 # TODO: the same about --capability=all
                 final_cmd += ['--keep-unit', '--capability=all']
+            if matches_source_version('>= 9.0'):
+                # Disable pseudo-TTY in container
+                final_cmd += ['--pipe']
             return final_cmd + ['-D', self.target] + binds + setenvs + cmd
 
     class CHROOT(_Implementation):