Address review comments

Author: hvitved

ruby/ql/lib/change-notes/2022-09-14-ruby-qll.md

@@ -1,4 +1,4 @@
 ---
 category: breaking
 ---
-* `import ruby` no longer brings the standard Ruby AST libarary into scope (it brings nothing into scope, so should no longer be used). Instead, import the AST library via `import codeql.ruby.AST`.
+* `import ruby` no longer brings the standard Ruby AST libarary into scope; it instead brings a module `Ast` into scope, which must be imported. Alternatively, it is also possible to import `codeql.ruby.AST`.

ruby/ql/lib/ruby.qll

@@ -1,9 +1,7 @@
 /**
- * Kept for backwards compatibility with e.g. quick-queries.
- *
- * Instead, import the relevant abstraction layer:
- * - `codeql.ruby.DataFlow` for data-flow queries.
- * - `codeql.ruby.CFG` for control-flow queries.
- * - `codeql.ruby.AST` for syntactic queries.
+ * Provides classes for working with Ruby programs.
  */
 
+import codeql.ruby.AST as Ast
+import codeql.ruby.CFG as Cfg
+import codeql.ruby.DataFlow // already defines its own wrapper module