[BUG] kinesis-source-integration-tests fails on every triggered

Describe the bug
The kinesis-source-integration-tests workflow is path-filtered (data-prepper-plugins/kinesis-source/** and root gradle files), so it only runs occasionally. Every run since at least late May has failed, across all Java matrix jobs, with:

KinesisSourceIT > ... FAILED
    org.mockito.exceptions.verification.WantedButNotInvoked at KinesisSourceIT.java:280

Recent failing runs on main:

• https://github.com/opensearch-project/data-prepper/actions/runs/28481066943 (2026-06-30)
• https://github.com/opensearch-project/data-prepper/actions/runs/27776440188 (2026-06-18)
• https://github.com/opensearch-project/data-prepper/actions/runs/27037279712 (2026-06-05)

It also fails the same way on PRs that trigger the path filter. On #6757 the workflow runs only because that PR registers a new module in the root settings.gradle, which matches the *gradle* path; the PR does not touch the kinesis source itself.

Expected behavior
The workflow should pass on main, or be fixed/disabled so it does not mask real failures on PRs.

Environment
GitHub Actions ubuntu runners, Java 11/17/21 matrix.

Start with KinesisSourceIT.java at line 280 and inspect the kinesis-source-integration-tests workflow configuration, including its path filter and Java 11/17/21 matrix. Reproduce the WantedButNotInvoked failure in a triggered workflow or local integration-test run, then verify that the workflow passes on main or is disabled without masking real PR failures.