Update Script_Header.adoc

Author: lihaoyi

website/docs/modules/ROOT/partials/Script_Header.adoc

@@ -2,7 +2,7 @@ This page documents the use cases and features of Mill's single-file {language}
 These are {language} modules with a single source file, with build configuration included
 in a header comment block at the top of the file.
 
-{language} scripts can be standalone or xref:#_project_moduledeps[part of a larger Mill project].
+{language} single-file scripts can be standalone or xref:#_project_moduledeps[part of a larger Mill project].
 They can be run via `./mill Foo.{language-ext}` from the command line, or have other tasks on
 them executed via `./mill Foo.{language-ext}:compile` or `./mill Foo.{language-ext}:assembly`.
 Apart from being limited to a single source file, single-file script modules otherwise