add 'nginx-admins-handbook'

- signed-off-by: trimstray <trimstray@gmail.com>

README.md

@@ -684,6 +684,7 @@ performance of any of your sites from across the globe.<br>
 &nbsp;&nbsp;:small_orange_diamond: <a href="https://github.com/NanXiao/strace-little-book"><b>strace-little-book</b></a> - a little book which introduces strace.<br>
 &nbsp;&nbsp;:small_orange_diamond: <a href="https://github.com/bagder/http2-explained"><b>http2-explained</b></a> - a detailed document explaining and documenting HTTP/2.<br>
 &nbsp;&nbsp;:small_orange_diamond: <a href="https://github.com/bagder/http3-explained"><b>http3-explained</b></a> - a document describing the HTTP/3 and QUIC protocols.<br>
+&nbsp;&nbsp;:small_orange_diamond: <a href="https://github.com/trimstray/nginx-admins-handbook"><b>Nginx Admin's Handbook</b></a> - describes how to improve NGINX performance, security and other important things.<br>
 &nbsp;&nbsp;:small_orange_diamond: <a href="https://infosec.mozilla.org/guidelines/openssh"><b>openssh guideline</b></a> - is to help operational teams with the configuration of OpenSSH server and client.<br>
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