Fix ansible_distribution on Ubuntu 10.04 (#31108)

The /etc/os-release based distro detection doesn't
seem to work for Ubuntu 10.04 (no /etc/os-release?).

So it was testing the next case which was /etc/lsb-release to
see if it is 'Mandriva'. Since the check for existence of
(/etc/lsb-release, Mandrive) was the first non-empty dist
file match, 'ansible_distribution' was being set to 'Mandriva'
expecting to be corrected by the data from the dist file content.

But since the dist file parsing for Mandriva didn't match for
Ubuntu 10.04 /etc/lsb-release _and_ there is no Debian specific
lsb-release check, 'ansible_distribution' stayed at 'Mandriva'
and the dist file checking loop keeps going and eventually off
the end of the list before finding a better match.

Adding a debian/ubuntu specific check for /etc/lsb-release after
the debian os-release sets the info correctly and stops further
checking of dist files.

Fixes #30693

lib/ansible/module_utils/facts/system/distribution.py

@@ -69,6 +69,7 @@ class DistributionFiles:
         {'path': '/etc/SuSE-release', 'name': 'SUSE'},
         {'path': '/etc/gentoo-release', 'name': 'Gentoo'},
         {'path': '/etc/os-release', 'name': 'Debian'},
+        {'path': '/etc/lsb-release', 'name': 'Debian'},
         {'path': '/etc/lsb-release', 'name': 'Mandriva'},
         {'path': '/etc/altlinux-release', 'name': 'Altlinux'},
         {'path': '/etc/sourcemage-release', 'name': 'SMGL'},

test/units/module_utils/test_distribution_version.py

@@ -418,6 +418,26 @@ BUG_REPORT_URL="http://bugs.debian.org/"
             "distribution_version": "16.04"
         }
     },
+    {
+        'name': "Ubuntu 10.04 guess",
+        'input':
+            {
+                '/etc/lsb-release': """DISTRIB_ID=Ubuntu
+DISTRIB_RELEASE=10.04
+DISTRIB_CODENAME=lucid
+DISTRIB_DESCRIPTION="Ubuntu 10.04.4 LTS
+"""
+            },
+        'platform.dist': ('Ubuntu', '10.04', 'lucid'),
+        'result':
+            {
+                'distribution': u'Ubuntu',
+                'distribution_major_version': u'10',
+                'distribution_release': u'lucid',
+                "os_family": "Debian",
+                'distribution_version': u'10.04'
+            }
+    },
     {
         'name': "Ubuntu 14.04",
         'input': {