[BUG] Remove logstash from downloads page

[derek-ho]

Describe the bug

On: https://opensearch.org/downloads.html, the logstash OSS plugin should be removed

Expected behavior

On: https://opensearch.org/downloads.html, the logstash OSS plugin should be removed

Screenshots

No response

To Reproduce

1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

Additional Details

Plugins
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Screenshots
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Host/Environment (please complete the following information):

• OS: [e.g. iOS]
• Version [e.g. 22]

Additional context
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[dblock]

[Catch All Triage - 1, 2, 3, 4, 5]