automation: Update mastodon-elasticsearch Docker tag to v8.9.0

This MR contains the following updates:

Package	Update	Change
mastodon-elasticsearch	minor	8.8.2 -> 8.9.0

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Release Notes

elastic/elasticsearch

v8.9.0: Elasticsearch 8.9.0

Compare Source

Downloads: https://elastic.co/downloads/elasticsearch Release notes: https://www.elastic.co/guide/en/elasticsearch/reference/8.9/release-notes-8.9.0.html

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