[v25.3.x] deps: update libxml2 from 2.14.5 to 2.14.6

[tyson-redpanda]

Backport of PR #29423

FIXES=CORE-15341

[tyson-redpanda]

I used the automatic merge conflict resolution of this lock file as guided here: https://bazel.build/external/lockfile#merge-conflicts

I'm expecting some builds would fail if this was incorrect, but please take a look for safety.

[IoannisRP]

looks correct 👍

[vbotbuildovich]

Retry command for Build#79776

please wait until all jobs are finished before running the slash command

/ci-repeat 1
skip-redpanda-build
skip-units
skip-rebase
tests/rptest/tests/read_replica_e2e_test.py::TestReadReplicaService.test_writes_forbidden@{"cloud_storage_type":1,"partition_count":10}

[vbotbuildovich]

CI test results

test results on build#79776

test_class	test_method	test_arguments	test_kind	job_url	test_status	passed	reason	test_history
DataTransformsLoggingTest	test_log_topic_integrity	null	integration	https://buildkite.com/redpanda/redpanda/builds/79776#019c0533-be21-4c55-bc88-31a36a8f5c9a	FLAKY	10/11	Test PASSES after retries.No significant increase in flaky rate(baseline=0.0000, p0=1.0000, reject_threshold=0.0100. adj_baseline=0.1000, p1=0.3487, trust_threshold=0.5000)	https://redpanda.metabaseapp.com/dashboard/87-tests?tab=142-dt-individual-test-history&test_class=DataTransformsLoggingTest&test_method=test_log_topic_integrity
TestReadReplicaService	test_writes_forbidden	{"cloud_storage_type": 1, "partition_count": 10}	integration	https://buildkite.com/redpanda/redpanda/builds/79776#019c0533-be21-4c55-bc88-31a36a8f5c9a	FLAKY	18/21	Test FAILS after retries.Significant increase in flaky rate(baseline=0.0050, p0=0.0045, reject_threshold=0.0100)	https://redpanda.metabaseapp.com/dashboard/87-tests?tab=142-dt-individual-test-history&test_class=TestReadReplicaService&test_method=test_writes_forbidden