Update libxml2 version to 2.14.4

[ubyte]

Changelog entry

libxml2 version updated from 2.9.13 -> 2.14.4

Changelog category

• Improvement

Description for reviewers

KIKIMR-23577

[github-actions]

🟢 2025-07-07 12:12:40 UTC The validation of the Pull Request description is successful.

[github-actions]

⚪ 2025-07-07 12:05:20 UTC Pre-commit check linux-x86_64-release-asan for f85650f has started.
⚪ 2025-07-07 12:05:31 UTC Artifacts will be uploaded here
⚪ 2025-07-07 12:08:51 UTC ya make is running...
🟡 2025-07-07 14:03:00 UTC Some tests failed, follow the links below. This fail is not in blocking policy yet

Test history | Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
14846	14475	0	150	195	26

🟢 2025-07-07 14:04:17 UTC Build successful.
🟢 2025-07-07 14:04:46 UTC ydbd size 3.9 GiB changed* by -593.2 KiB, which is <= 0 Bytes vs main: OK

ydbd size dash	main: 2674df3	merge: f85650f	diff	diff %
ydbd size	4 200 044 824 Bytes	4 199 437 352 Bytes	-593.2 KiB	-0.014%
ydbd stripped size	1 455 242 360 Bytes	1 454 731 544 Bytes	-498.8 KiB	-0.035%

^{*please be aware that the difference is based on comparing your commit and the last completed build from the post-commit, check comparation}

[github-actions]

⚪ 2025-07-07 12:05:30 UTC Pre-commit check linux-x86_64-relwithdebinfo for f85650f has started.
⚪ 2025-07-07 12:05:42 UTC Artifacts will be uploaded here
⚪ 2025-07-07 12:09:05 UTC ya make is running...
🟡 2025-07-07 13:32:26 UTC Some tests failed, follow the links below. Going to retry failed tests...

Test history | Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
37243	34489	0	9	2695	50

⚪ 2025-07-07 13:35:45 UTC ya make is running... (failed tests rerun, try 2)
🟢 2025-07-07 13:48:43 UTC Tests successful.

Test history | Ya make output | Test bloat | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
826 (only retried tests)	744	0	0	44	38

🟢 2025-07-07 13:48:54 UTC Build successful.
🟢 2025-07-07 13:49:16 UTC ydbd size 2.2 GiB changed* by -147.9 KiB, which is <= 0 Bytes vs main: OK

ydbd size dash	main: 2674df3	merge: f85650f	diff	diff %
ydbd size	2 387 893 536 Bytes	2 387 742 056 Bytes	-147.9 KiB	-0.006%
ydbd stripped size	499 612 200 Bytes	499 488 928 Bytes	-120.4 KiB	-0.025%

^{*please be aware that the difference is based on comparing your commit and the last completed build from the post-commit, check comparation}