minor #9741 [Console] Fix SymfonyStyle::ask usage (liviubalan, javiereguiluz)

This PR was merged into the 2.7 branch.

Discussion
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[Console] Fix SymfonyStyle::ask usage

Use function "ctype_digit" instead of "is_integer" because "$number" is not an integer value, but a string

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Commits
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9bb23e1 Use is_numeric()
38bcfcb [Console] Fix SymfonyStyle::ask usage

Author: javiereguiluz

console/style.rst

@@ -238,11 +238,11 @@ User Input Methods
     the third argument::
 
         $io->ask('Number of workers to start', 1, function ($number) {
-            if (!is_integer($number)) {
-                throw new \RuntimeException('You must type an integer.');
+            if (!is_numeric($number)) {
+                throw new \RuntimeException('You must type a number.');
             }
 
-            return $number;
+            return (int) $number;
         });
 
 :method:`Symfony\\Component\\Console\\Style\\SymfonyStyle::askHidden`