[Backport 7.60.x] Bump confluent-kafka to 2.6.1 to address CVE

[datadog-agent-integrations-bot]

Backport 1435476 from #19099.

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What does this PR do?

https://datadoghq.atlassian.net/browse/AI-4128

This updates confluent-kafka builders and dependency to address this CVE

https://github.com/confluentinc/librdkafka/releases/tag/v2.6.1

Motivation

• Upgrade Linux dependencies: OpenSSL 3.0.15, CURL 8.10.1 (Upgrade linux dependencies confluentinc/librdkafka#4875).
• Upgrade Windows dependencies: MSVC runtime to 14.40.338160.0,
  zstd 1.5.6, zlib 1.3.1, OpenSSL 3.3.2, CURL 8.10.1 (Upgrade msvcr140 and vcpkg dependencies confluentinc/librdkafka#4872).

Review checklist (to be filled by reviewers)

• Feature or bugfix MUST have appropriate tests (unit, integration, e2e)
• Add the qa/skip-qa label if the PR doesn't need to be tested during QA.
• If you need to backport this PR to another branch, you can add the backport/<branch-name> label to the PR and it will automatically open a backport PR once this one is merged

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 87.02%. Comparing base (a242726) to head (341ebba).
Report is 3 commits behind head on 7.60.x.

Additional details and impacted files

Flag	Coverage Δ
activemq	?
cassandra	?
hive	?
hivemq	?
hudi	?
ignite	?
jboss_wildfly	?
kafka	?
kafka_consumer	93.58% <ø> (+2.10%)	⬆️
presto	?
solr	?

Flags with carried forward coverage won't be shown. Click here to find out more.

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