minor #17356 Remove akamai broken link (elliotbruneel)

This PR was merged into the 4.4 branch.

Discussion
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Remove akamai broken link

The link of the article is broken, according to archive.org the last version available was in July 2021: https://web.archive.org/web/20210729163732/https://blogs.akamai.com/2017/03/http2-server-push-the-what-how-and-why.html

The article seems to be no longer available

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Commits
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58ede1b Remove akamai broken link

Author: javiereguiluz

web_link.rst

@@ -100,7 +100,7 @@ According to `the Preload specification`_, when an HTTP/2 server detects that
 the original (HTTP 1.x) response contains this HTTP header, it will
 automatically trigger a push for the related file in the same HTTP/2 connection.
 
-Popular proxy services and CDNs including `Cloudflare`_, `Fastly`_ and `Akamai`_
+Popular proxy services and CDNs including `Cloudflare`_ and `Fastly`_
 also leverage this feature. It means that you can push resources to clients and
 improve performance of your applications in production right now.
 
@@ -187,6 +187,5 @@ You can also add links to the HTTP response directly from controllers and servic
 .. _`the Preload specification`: https://www.w3.org/TR/preload/#server-push-http-2
 .. _`Cloudflare`: https://blog.cloudflare.com/announcing-support-for-http-2-server-push-2/
 .. _`Fastly`: https://docs.fastly.com/en/guides/http2-server-push
-.. _`Akamai`: https://blogs.akamai.com/2017/03/http2-server-push-the-what-how-and-why.html
 .. _`link defined in the HTML specification`: https://html.spec.whatwg.org/dev/links.html#linkTypes
 .. _`PSR-13`: https://www.php-fig.org/psr/psr-13/