[bitnami/kafka] Fix jmx-exporter scrape path

[horihel]

Description of the change

Changes the scrape path of the jmx-exporter ServiceMonitor to /metrics, as jmx-exporter apparently changed the path in a major version upgrade. Fixes #27546

same for prometheus annotations, as it's the same problem.

Benefits

Metrics work again.

Possible drawbacks

Applicable issues

• fixes #27546

Additional information

Checklist

• [X] Chart version bumped in Chart.yaml according to semver. This is not necessary when the changes only affect README.md files.
• [X] Title of the pull request follows this pattern [bitnami/<name_of_the_chart>] Descriptive title
• [X] All commits signed off and in agreement of Developer Certificate of Origin (DCO)