cleanup(apm): remove old rum deprecations (#4644)

deprecated rum config options have been removed in 8.0
so they no longer apply.
remove the deprecated options from docs

(cherry picked from commit 944662f)

docs/en/observability/apm/configure/rum.asciidoc

@@ -162,45 +162,8 @@ Search source maps stored in an older version with this setting.
 
 Default: `"apm-*-sourcemap*"`
 
-[float]
-[[apm-rum-deprecated]]
-== Deprecated configuration options
-
-[float]
-[[apm-event_rate.limit]]
-=== `event_rate.limit`
-
-deprecated::[7.15.0, Replaced by <<apm-config-auth-anon-event-limit>>.]
-
-The maximum number of events allowed per second, per agent IP address.
-
-Default: `300`
-
-[float]
-=== `event_rate.lru_size`
-
-deprecated::[7.15.0, Replaced by <<apm-config-auth-anon-ip-limit>>.]
-
-The number of unique IP addresses to track in an LRU cache.
-IP addresses in the cache will be rate limited according to the <<apm-config-auth-anon-event-limit>> setting.
-Consider increasing this default if your site has many concurrent clients.
-
-Default: `1000`
-
-[float]
-[[apm-rum-allow-service-names]]
-=== `allow_service_names`
-
-deprecated::[7.15.0, Replaced by <<apm-config-auth-anon-allow-service>>.]
-A list of permitted service names for RUM support.
-Names in this list must match the agent's `service.name`.
-This can be set to restrict RUM events to those with one of a set of known service names,
-in order to limit the number of service-specific indices or data streams created.
-
-Default: Not set (any service name is accepted)
-
 [float]
 == Ingest pipelines
 
 The default APM Server pipeline includes processors that enrich RUM data prior to indexing in {es}.
-See <<apm-ingest-pipelines>> for details on how to locate, edit, or disable this preprocessing.
+See <<apm-ingest-pipelines>> for details on how to locate, edit, or disable this preprocessing.