[DOCS] Add "delete index template" API docs (#46101)

docs/reference/indices.asciidoc

@@ -49,6 +49,7 @@ index settings, aliases, mappings, and index templates.
 [float]
 [[index-templates]]
 === Index templates:
+* <<indices-delete-template>>
 * <<indices-template-exists>>
 * <<indices-templates>>
 
@@ -114,6 +115,8 @@ include::indices/get-settings.asciidoc[]
 
 include::indices/analyze.asciidoc[]
 
+include::indices/delete-index-template.asciidoc[]
+
 include::indices/template-exists.asciidoc[]
 
 include::indices/templates.asciidoc[]

docs/reference/indices/delete-index-template.asciidoc

@@ -0,0 +1,54 @@
+[[indices-delete-template]]
+=== Delete index template API
+++++
+<titleabbrev>Delete template index</titleabbrev>
+++++
+
+Deletes an existing index.
+
+////
+[source,js]
+--------------------------------------------------
+PUT _template/template_1
+{
+ "index_patterns" : ["te*"],
+  "settings": {
+    "number_of_shards": 1
+  }
+}
+--------------------------------------------------
+// CONSOLE
+// TESTSETUP
+////
+
+[source,js]
+--------------------------------------------------
+DELETE /_template/template_1
+--------------------------------------------------
+// CONSOLE
+
+
+[[delete-template-api-request]]
+==== {api-request-title}
+
+`DELETE /_template/<index-template>`
+
+
+[[delete-template-api-desc]]
+==== {api-description-title}
+
+Use the delete index template API to delete one or more index templates
+
+include::templates.asciidoc[tag=index-template-def]
+
+
+[[delete-template-api-path-params]]
+==== {api-path-parms-title}
+
+include::{docdir}/rest-api/common-parms.asciidoc[tag=index-template]
+
+
+[[delete-template-api-query-params]]
+==== {api-query-parms-title}
+
+include::{docdir}/rest-api/common-parms.asciidoc[tag=timeoutparms]