minor #13951 Tweak security checker wording (tucksaun)

This PR was merged into the 3.4 branch.

Discussion
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Tweak security checker wording

"Cloning" is not accurate anymore as the command now uses GitHub HTTP API

Commits
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167f58b Tweak security checker wording

Author: javiereguiluz

security/security_checker.rst

@@ -15,7 +15,7 @@ file to find known security vulnerabilities in your installed dependencies:
 
 A good security practice is to execute this command regularly to be able to
 update or replace compromised dependencies as soon as possible. The security
-check is done locally by cloning the `security advisories database`_ published
+check is done locally by fetching the `security advisories database`_ published
 by the FriendsOfPHP organization, so your ``composer.lock`` file is not sent on
 the network.