Tests override-true-all-profile fail with new libxml2

[jan-cerny]

Description of problem:

Some of our tests from group verify-ssg-${PRODUCT}-ds.xml-override-true-all-profile-titles or verify-ssg-${PRODUCT}-ds.xml-override-true-all-profile-descriptions started to fail.

A problem caused by a change of behavior of the xmllint utility in https://gitlab.gnome.org/GNOME/libxml2/-/commit/e85f9b98a5389c69167176ae6600091e719ec38f. This change seems to be present in libxml2 >= 2.11 and it currently affects Rawhide.

This problem has been discovered in CI results in https://src.fedoraproject.org/rpms/openscap/pull-request/21 and also in #11047

SCAP Security Guide Version:

current upstream master as of 2023-09-06 as of HEAD 7610bb9

Operating System Version:

Fedora Rawhide
libxml2-2.11.5-1.fc40.x86_64

Steps to Reproduce:

1. build a product, eg. ./build_product rhel9
2. cd build
3. Run tests from the affected group, eg. ctest --verbose -R verify-ssg-rhel9-ds.xml-override-true-all-profile-titles

Actual Results:

UpdateCTestConfiguration  from :/root/content/build/DartConfiguration.tcl
UpdateCTestConfiguration  from :/root/content/build/DartConfiguration.tcl
Test project /root/content/build
Constructing a list of tests
Done constructing a list of tests
Updating test list for fixtures
Added 0 tests to meet fixture requirements
Checking test dependency graph...
Checking test dependency graph end
test 37
    Start 37: verify-ssg-rhel9-ds.xml-override-true-all-profile-titles

37: Test command: /usr/bin/xmllint "--xpath" "//*[local-name()="Profile"]/*[local-name()="title"][not(@override="true")]" "/root/content/build/ssg-rhel9-ds.xml"
37: Working Directory: /root/content/build/rhel9
37: Test timeout computed to be: 10000000
37: XPath set is empty
1/1 Test #37: verify-ssg-rhel9-ds.xml-override-true-all-profile-titles ...***Failed    0.25 sec

0% tests passed, 1 tests failed out of 1

Label Time Summary:
quick    =   0.25 sec*proc (1 test)

Total Test time (real) =   0.26 sec

The following tests FAILED:
	 37 - verify-ssg-rhel9-ds.xml-override-true-all-profile-titles (Failed)
Errors while running CTest
Output from these tests are in: /root/content/build/Testing/Temporary/LastTest.log
Use "--rerun-failed --output-on-failure" to re-run the failed cases verbosely.

Expected Results:

tests don't fail

Additional Information/Debugging Steps:

The problem is the return code change.

This is with the new libxml2:

[root@vm-10-0-185-97 build]# /usr/bin/xmllint "--xpath" "//*[local-name()="Profile"]/*[local-name()="title"][not(@override="true")]" "ssg-rhel9-ds.xml"
XPath set is empty
[root@vm-10-0-185-97 build]# echo $?
0

And this is with old libxml2:

[jcerny@fedora build{master}]$ /usr/bin/xmllint "--xpath" "//*[local-name()="Profile"]/*[local-name()="title"][not(@override="true")]" "ssg-rhel9-ds.xml"
XPath set is empty
[jcerny@fedora build{master}]$ echo $?
10