Remove relontes entry for Kibana #142369 in 8.6 (elastic#2506)

release-notes/release-notes-8.6.asciidoc

@@ -94,7 +94,6 @@ The 8.6.0 release adds the following new and notable features.
 * Differentiate kubernetes integration multipage experience {kibana-pull}145224[#145224]
 * Add prerelease toggle to Integrations list {kibana-pull}143853[#143853]
 * Add link to allow users to skip multistep add integration workflow {kibana-pull}143279[#143279]
-* Add new action for single agents to request diagnostics {kibana-pull}142369[#142369]
 
 {agent}::
 * Upgrade Node to version 18.12.0 {agent-pull}1657[#1657]