[doc] we don't use `check_lucene` anymore in plugins

docs/plugins/plugin-script.asciidoc

@@ -223,18 +223,3 @@ plugin.mandatory: mapper-attachments,lang-groovy
 
 For safety reasons, a node will not start if it is missing a mandatory plugin.
 
-[float]
-=== Lucene version dependent plugins
-
-For some plugins, such as analysis plugins, a specific major Lucene version is
-required to run. In that case, the plugin provides in its
-`es-plugin.properties` file the Lucene version for which the plugin was built for.
-
-If present at startup the node will check the Lucene version before loading
-the plugin. You can disable that check using
-
-[source,yaml]
---------------------------------------------------
-plugins.check_lucene: false
---------------------------------------------------
-