remove oreilly email from code examples bit

Author: hjwp

preface.asciidoc

@@ -254,8 +254,6 @@ https://github.com/hjwp/book-example/tree/chapter_03_unit_test_first_view[]).
 You'll find a full list, and some suggestions on ways of working with this
 repository, in <<appendix_github_links>>.
 
-If you have a technical question or a problem using the code examples, please send email to pass:[<a class="email" href="mailto:[email protected]"><em>[email protected]</em></a>].
-
 This book is here to help you get your job done. In general, if example code is offered with this book, you may use it in your programs and documentation. You do not need to contact us for permission unless you’re reproducing a significant portion of the code. For example, writing a program that uses several chunks of code from this book does not require permission. Selling or distributing examples from O’Reilly books does require permission. Answering a question by citing this book and quoting example code does not require permission. Incorporating a significant amount of example code from this book into your product’s documentation does require permission.
 
 We appreciate, but do not require, attribution. An attribution usually includes