minor #18011 [Validator] Remove texts about require php 8.1 (MrYamous)

This PR was merged into the 6.2 branch.

Discussion
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[Validator] Remove texts about require php 8.1

Commits
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f5cb7e0 [Validator] remove mention require php 8.1

Author: OskarStark

reference/constraints/All.rst

@@ -25,7 +25,6 @@ entry in that array:
 
         use Symfony\Component\Validator\Constraints as Assert;
 
-        // IMPORTANT: nested attributes require PHP 8.1 or higher
         class User
         {
             #[Assert\All([

reference/constraints/AtLeastOneOf.rst

@@ -29,7 +29,6 @@ The following constraints ensure that:
 
         use Symfony\Component\Validator\Constraints as Assert;
 
-        // IMPORTANT: nested attributes requires PHP 8.1 or higher
         class Student
         {
             #[Assert\AtLeastOneOf([

reference/constraints/Collection.rst

@@ -58,7 +58,6 @@ following:
 
         use Symfony\Component\Validator\Constraints as Assert;
 
-        // IMPORTANT: nested attributes requires PHP 8.1 or higher
         class Author
         {
             #[Assert\Collection(

reference/constraints/Sequentially.rst

@@ -44,7 +44,6 @@ You can validate each of these constraints sequentially to solve these issues:
         use App\Validator\Constraints as AcmeAssert;
         use Symfony\Component\Validator\Constraints as Assert;
 
-        // IMPORTANT: nested attributes requires PHP 8.1 or higher
         class Place
         {
             #[Assert\Sequentially([