[DOCS] Move common scripting use cases up a level (elastic#73445)

docs/reference/scripting.asciidoc

@@ -53,6 +53,8 @@ include::scripting/painless.asciidoc[]
 
 include::scripting/using.asciidoc[]
 
+include::scripting/common-script-uses.asciidoc[]
+
 include::scripting/fields.asciidoc[]
 
 include::scripting/security.asciidoc[]

docs/reference/scripting/common-script-uses.asciidoc

@@ -1,12 +1,14 @@
 [[common-script-uses]]
-=== Common scripting use cases
+== Common scripting use cases
 You can write a script to do almost anything, and sometimes, that's
 the trouble. It's challenging to know what's possible with scripts,
 so the following examples address common uses cases where scripts are
 really helpful.
 
+* <<scripting-field-extraction,Field extraction>>
+
 [[scripting-field-extraction]]
-==== Field extraction
+=== Field extraction
 The goal of field extraction is simple; you have fields in your data with a bunch of
 information, but you only want to extract pieces and parts.
 
@@ -73,7 +75,7 @@ POST /my-index/_bulk?refresh
 
 [discrete]
 [[field-extraction-ip]]
-===== Extract an IP address from a log message (Grok)
+==== Extract an IP address from a log message (Grok)
 If you want to retrieve results that include `clientip`, you can add that
 field as a runtime field in the mapping. The following runtime script defines a
 grok pattern that extracts structured fields out of the `message` field. 

docs/reference/scripting/using.asciidoc

@@ -566,4 +566,3 @@ DELETE /_ingest/pipeline/my_test_scores_pipeline
 
 ////
 
-include::common-script-uses.asciidoc[]