[8.x] [Dev Server] Remove dead code (#193736) (#193759)

# Backport

This will backport the following commits from `main` to `8.x`:
- [[Dev Server] Remove dead code
(#193736)](#193736)

<!--- Backport version: 9.4.3 -->

### Questions ?
Please refer to the [Backport tool
documentation](https://github.com/sqren/backport)

<!--BACKPORT [{"author":{"name":"Alejandro Fernández
Haro","email":"[email protected]"},"sourceCommit":{"committedDate":"2024-09-23T17:01:08Z","message":"[Dev
Server] Remove dead code
(#193736)","sha":"e6e170e687a2221ebdcf49c0942cf6e40aed9b59","branchLabelMapping":{"^v9.0.0$":"main","^v8.16.0$":"8.x","^v(\\d+).(\\d+).\\d+$":"$1.$2"}},"sourcePullRequest":{"labels":["Team:Operations","technical
debt","release_note:skip","v9.0.0","backport:prev-minor"],"title":"[Dev
Server] Remove dead
code","number":193736,"url":"https://github.com/elastic/kibana/pull/193736","mergeCommit":{"message":"[Dev
Server] Remove dead code
(#193736)","sha":"e6e170e687a2221ebdcf49c0942cf6e40aed9b59"}},"sourceBranch":"main","suggestedTargetBranches":[],"targetPullRequestStates":[{"branch":"main","label":"v9.0.0","branchLabelMappingKey":"^v9.0.0$","isSourceBranch":true,"state":"MERGED","url":"https://github.com/elastic/kibana/pull/193736","number":193736,"mergeCommit":{"message":"[Dev
Server] Remove dead code
(#193736)","sha":"e6e170e687a2221ebdcf49c0942cf6e40aed9b59"}}]}]
BACKPORT-->

Co-authored-by: Alejandro Fernández Haro <[email protected]>

packages/kbn-cli-dev-mode/src/dev_server.ts

@@ -196,16 +196,6 @@ export class DevServer {
               this.phase$.next('listening');
               this.ready$.next(true);
             }
-
-            // TODO: remove this once Pier is done migrating log rotation to KP
-            if (msg === 'RELOAD_LOGGING_CONFIG_FROM_SERVER_WORKER') {
-              // When receive that event from server worker
-              // forward a reloadLoggingConfig message to parent
-              // and child proc. This is only used by LogRotator service
-              // when the cluster mode is enabled
-              process.emit('message' as any, { reloadLoggingConfig: true } as any);
-              proc.send({ reloadLoggingConfig: true });
-            }
           }),
           takeUntil(exit$)
         );