Fixes /guide to /docs 404s

[KOTungseth]

Fixes the following mappings to resolve /guide to /docs 404s:

• https://www.elastic.co/guide/en/elasticsearch/client/net-api/8.19/migration-guide.html
• https://www.elastic.co/guide/en/observability/8.19/elastic-entity-model.html
• https://www.elastic.co/guide/en/apm/agent/android/0.x/release-notes.html
• https://www.elastic.co/guide/en/observability/8.19/inventory.html
• https://www.elastic.co/guide/en/observability/8.19/monitor-java-app.html
• https://www.elastic.co/guide/en/observability/8.17/profiling-known-issues.html

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