remove unused docs substitution variables (elastic#134225)

Author: shainaraskas

docs/docset.yml

@@ -35,7 +35,6 @@ subs:
   api-prereq-title:   "Prerequisites"
   api-description-title:   "Description"
   api-path-parms-title:   "Path parameters"
-  api-query-parms-title:   "Query parameters"
   api-request-body-title:   "Request body"
   api-examples-title:   "Examples"
   ecloud:   "Elastic Cloud"
@@ -49,7 +48,6 @@ subs:
   serverless-full:   "Elastic Cloud Serverless"
   serverless-short:   "Serverless"
   es-serverless:   "Elasticsearch Serverless"
-  ess-utm-params:   "?page=docs&placement=docs-body"
   cloud-only:   "This feature is designed for indirect use by Elasticsearch Service, Elastic Cloud Enterprise, and Elastic Cloud on Kubernetes. Direct use is not supported."
   security-app:   "Elastic Security app"
   stack-monitor-app:   "Stack Monitoring"
@@ -87,13 +85,10 @@ subs:
   search-snaps:   "searchable snapshots"
   slm:   "snapshot lifecycle management"
   slm-init:   "SLM"
-  dfeed:   "datafeed"
   dfeeds:   "datafeeds"
   dfeeds-cap:   "Datafeeds"
   anomaly-detect:   "anomaly detection"
   anomaly-jobs:   "anomaly detection jobs"
-  dataframe:   "data frame"
-  dataframe-cap:   "Data frame"
   transform:   "transform"
   transforms:   "transforms"
   transforms-cap:   "Transforms"
@@ -113,4 +108,3 @@ subs:
   nlp:   "natural language processing"
   index-manage-app:   "Index Management"
   connectors-app:   "Connectors"
-  ingest-pipelines-app:   "Ingest Pipelines"