Docs: Logstash 7.17.28 release docs

[karenzone]

Logstash release manager: @jsvd
Logstash tech writer: @karenzone
Docs release manager: @natasha-moore-elastic

Logstash release docs

• Release notes: Release notes for 7.17.28 #17112
  • Add link to docs release issue: https://github.com/elastic/dev/issues/3024
• Update plugin docs: updated docs for 7.17 logstash-docs#1809