minor #10534 Updating security_checker.rst (shreypuranik)

This PR was submitted for the 4.1 branch but it was merged into the 2.8 branch instead (closes #10534).

Discussion
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Updating security_checker.rst

Updating with an example scenario of how the security checker can be integrated

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Commits
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108bf1a Updating security_checker.rst

Author: javiereguiluz

security/security_checker.rst

@@ -22,7 +22,9 @@ FriendsOfPHP organization.
 
     The ``security:check`` command terminates with a non-zero exit code if
     any of your dependencies is affected by a known security vulnerability.
-    Therefore, you can easily integrate it in your build process.
+    Therefore, you can easily integrate it in your build process, so that 
+    all dependencies are checked for known security vulnerabilities each 
+    time that the project is built. 
 
 .. note::