minor #1282 doc: v2 use PHP 8.0 (bchatard)

This PR was merged into the main branch.

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doc: v2 use PHP 8.0

Update README, according to v2 change (see `composer.json`)

Commits
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e3d13ec doc: v2 use PHP 8.0

Author: javiereguiluz

README.md

@@ -7,7 +7,7 @@ to develop applications following the [Symfony Best Practices][1].
 Requirements
 ------------
 
-  * PHP 7.3 or higher;
+  * PHP 8.0.2 or higher;
   * PDO-SQLite PHP extension enabled;
   * and the [usual Symfony application requirements][2].