Update securing-http-traffic-upstream.md (#497)

Co-authored-by: Mike Jang <[email protected]>

Author: melissa-m-huang

content/nginx/admin-guide/security-controls/securing-http-traffic-upstream.md

@@ -20,7 +20,7 @@ This article explains how to encrypt HTTP traffic between NGINX and a upstream g
 
 ## Obtaining SSL Server Certificates
 
-You can purchase a server certificate from a trusted certificate authority (CA), or your can create own internal CA with an [OpenSSL](https://www.openssl.org/) library and generate your own certificate. The server certificate together with a private key should be placed on each upstream server.
+Purchase a server certificate from a trusted certificate authority (CA), or create your own internal CA with an [OpenSSL](https://www.openssl.org/) library and generate your own certificate. The server certificate together with a private key should be placed on each upstream server.
 
 <span id="client_certs"></span>
 ## Obtaining an SSL Client Certificate