minor #7791 Fixed broken links for nginx & FastCgiExternalServer (finchmeister)

This PR was submitted for the 3.2 branch but it was merged into the 2.7 branch instead (closes #7791).

Discussion
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Fixed broken links for nginx & FastCgiExternalServer

Commits
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b8d01ec Fixed broken links for nginx & FastCgiExternalServer

Author: xabbuh

setup/web_server_configuration.rst

@@ -339,5 +339,5 @@ The **minimum configuration** to get your application running under Nginx is:
 For advanced Nginx configuration options, read the official `Nginx documentation`_.
 
 .. _`Apache documentation`: http://httpd.apache.org/docs/
-.. _`FastCgiExternalServer`: http://www.fastcgi.com/mod_fastcgi/docs/mod_fastcgi.html#FastCgiExternalServer
-.. _`Nginx documentation`: http://wiki.nginx.org/Symfony
+.. _`FastCgiExternalServer`: https://docs.oracle.com/cd/B31017_01/web.1013/q20204/mod_fastcgi.html#FastCgiExternalServer
+.. _`Nginx documentation`: https://www.nginx.com/resources/wiki/start/topics/recipes/symfony/