minor #30549 [HttpClient] Make exceptions public (dunglas)

This PR was squashed before being merged into the 4.3-dev branch (closes #30549).

Discussion
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[HttpClient] Make exceptions public

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | no<!-- don't forget to update src/**/CHANGELOG.md files -->
| BC breaks?    | no     <!-- see https://symfony.com/bc -->
| Deprecations? | no <!-- don't forget to update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Tests pass?   | yes    <!-- please add some, will be required by reviewers -->
| Fixed tickets | #...   <!-- #-prefixed issue number(s), if any -->
| License       | MIT
| Doc PR        | n/a

Makes it easier to implement the interface. See api-platform/core#2608

Commits
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928d774e4a [HttpClient] Make exceptions public

src/Symfony/Component/HttpClient/Exception/ClientException.php

@@ -18,7 +18,7 @@ use Symfony\Contracts\HttpClient\Exception\ClientExceptionInterface;
  *
  * @author Nicolas Grekas <p@tchwork.com>
  *
- * @internal
+ * @experimental in 4.3
  */
 final class ClientException extends \RuntimeException implements ClientExceptionInterface
 {

src/Symfony/Component/HttpClient/Exception/InvalidArgumentException.php

@@ -16,7 +16,7 @@ use Symfony\Contracts\HttpClient\Exception\TransportExceptionInterface;
 /**
  * @author Nicolas Grekas <p@tchwork.com>
  *
- * @internal
+ * @experimental in 4.3
  */
 final class InvalidArgumentException extends \InvalidArgumentException implements TransportExceptionInterface
 {

src/Symfony/Component/HttpClient/Exception/JsonException.php

@@ -18,7 +18,7 @@ use Symfony\Contracts\HttpClient\Exception\TransportExceptionInterface;
  *
  * @author Nicolas Grekas <p@tchwork.com>
  *
- * @internal
+ * @experimental in 4.3
  */
 final class JsonException extends \JsonException implements TransportExceptionInterface
 {

src/Symfony/Component/HttpClient/Exception/RedirectionException.php

@@ -18,7 +18,7 @@ use Symfony\Contracts\HttpClient\Exception\RedirectionExceptionInterface;
  *
  * @author Nicolas Grekas <p@tchwork.com>
  *
- * @internal
+ * @experimental in 4.3
  */
 final class RedirectionException extends \RuntimeException implements RedirectionExceptionInterface
 {

src/Symfony/Component/HttpClient/Exception/ServerException.php

@@ -18,7 +18,7 @@ use Symfony\Contracts\HttpClient\Exception\ServerExceptionInterface;
  *
  * @author Nicolas Grekas <p@tchwork.com>
  *
- * @internal
+ * @experimental in 4.3
  */
 final class ServerException extends \RuntimeException implements ServerExceptionInterface
 {

src/Symfony/Component/HttpClient/Exception/TransportException.php

@@ -16,7 +16,7 @@ use Symfony\Contracts\HttpClient\Exception\TransportExceptionInterface;
 /**
  * @author Nicolas Grekas <p@tchwork.com>
  *
- * @internal
+ * @experimental in 4.3
  */
 final class TransportException extends \RuntimeException implements TransportExceptionInterface
 {