test: Fix SNI validation failures with Druid 35.0.1

[dervoeti]

Description

Druid 35.0.1 introduced strict SNI host checking (enabled by default) as part of the Jetty 12 upgrade. Test scripts were using short hostnames (e.g., druid-coordinator-default-headless) which don't match the TLS certificates that contain only FQDNs (e.g., *.svc.cluster.local), causing "HTTP ERROR 400 Invalid SNI" failures.

This fixes test failures for all Druid 35.0.1 tests that use TLS.

This test failed before on my local machine, with the fix from this PR it works:

--- PASS: kuttl/harness/ingestion-s3-ext_druid-latest-35.0.1_zookeeper-latest-3.9.4_hadoop-3.4.2_openshift-false (326.11s)

Definition of Done Checklist

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Author

• Changes are OpenShift compatible
• CRD changes approved
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Reviewer

• Code contains useful comments
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• (Integration-)Test cases added
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• Changelog updated
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Acceptance

• Feature Tracker has been updated
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• Release note snippet added
• Add type/deprecation label & add to the deprecation schedule
• Add type/experimental label & add to the experimental features tracker