minor #19652 Update PHP version in "Install the Software Stack" section (AurelienPillevesse)

This PR was merged into the 6.4 branch.

Discussion
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Update PHP version in "Install the Software Stack" section

Commits
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ba0378c Update pull_requests.rst

Author: javiereguiluz

contributing/code/pull_requests.rst

@@ -31,7 +31,7 @@ Before working on Symfony, setup a friendly environment with the following
 software:
 
 * Git;
-* PHP version 7.2.5 or above.
+* PHP version 8.1 or above.
 
 Configure Git
 ~~~~~~~~~~~~~