Add QueryBurn to community monitoring integrations

[ofeliacode]

Summary

Adds QueryBurn to the community monitoring solutions section.

QueryBurn is an open source read-only agent that scans system.query_log and sends Telegram alerts for expensive
ClickHouse queries.

This follows maintainer feedback to add it around the ClickHouse integrations docs.

Checklist

• Delete items not relevant to your PR
• URL changes should add a redirect to the old URL via
  https://github.com/ClickHouse/clickhouse-docs/blob/main/vercel.json
• If adding a new integration page, also add an entry to the integrations list here:
  https://github.com/ClickHouse/clickhouse-docs/blob/main/docs/integrations/index.mdx

[vercel]

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