Fix path to docs in README raw text

docs/src/main/ruby/generate_readme.sh

@@ -17,7 +17,7 @@ end
 file = ARGV[0] if ARGV.length>0
 
 srcDir = File.dirname(file)
-out = "// Do not edit this file (e.g. go instead to src/main/asciidoc)\n\n"
+out = "// Do not edit this file (e.g. go instead to docs/src/main/asciidoc)\n\n"
 doc = Asciidoctor.load_file file, safe: :safe, parse: false, attributes: 'allow-uri-read'
 out << doc.reader.read