minor #33808 [Console] Throw a TypeError for non-int return value calling Command::execute() (jschaedl)

This PR was merged into the 5.0-dev branch.

Discussion
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[Console] Throw a TypeError for non-int return value calling Command::execute()

| Q             | A
| ------------- | ---
| Branch?       | 5.0
| Bug fix?      | no
| New feature?  | no <!-- please update src/**/CHANGELOG.md files -->
| Deprecations? | yes <!-- please update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Tickets       | Fix #33747 <!-- prefix each issue number with "Fix #", if any -->
| License       | MIT
| Doc PR        | - <!-- required for new features -->

### Todo

- [x] needs to be rebased after 4.4 was merged into master (see: https://github.com/symfony/symfony/pull/33805)

Commits
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b3a3b0c235 [Console] Throw a TypeError for non-int return values on calling Command::execute()

src/Symfony/Component/Console/CHANGELOG.md

@@ -10,6 +10,7 @@ CHANGELOG
  * removed `TableStyle::getHorizontalBorderChar()` method in favor of `TableStyle::getBorderChars()`
  * removed `TableStyle::setVerticalBorderChar()` method in favor of `TableStyle::setVerticalBorderChars()`
  * removed `TableStyle::getVerticalBorderChar()` method in favor of `TableStyle::getBorderChars()`
+ * removed support for returning `null` from `Command::execute()`, return `0` instead
  * `ProcessHelper::run()` accepts only `array|Symfony\Component\Process\Process` for its `command` argument
  * `Application::setDispatcher` accepts only `Symfony\Contracts\EventDispatcher\EventDispatcherInterface` 
     for its `dispatcher` argument

src/Symfony/Component/Console/Command/Command.php

@@ -255,7 +255,7 @@ class Command
             $statusCode = $this->execute($input, $output);
 
             if (!\is_int($statusCode)) {
-                @trigger_error(sprintf('Return value of "%s::execute()" should always be of the type int since Symfony 4.4, %s returned.', \get_class($this), \gettype($statusCode)), E_USER_DEPRECATED);
+                throw new \TypeError(sprintf('Return value of "%s::execute()" must be of the type int, %s returned.', \get_class($this), \gettype($statusCode)));
             }
         }