remove useless serialize union selector

Author: mtarld

src/Symfony/Component/SerDes/Context/SerializeContext.php

@@ -49,14 +49,6 @@ public function withJsonEncodeFlags(int $flags): self
         return new self(['json_encode_flags' => $flags] + $this->options);
     }
 
-    /**
-     * @param array<string, string> $unionSelector
-     */
-    public function withUnionSelector(array $unionSelector): self
-    {
-        return new self(['union_selector' => $unionSelector] + $this->options);
-    }
-
     /**
      * @param ObjectHookInterface|callable(string, string, array<string, mixed>): array{type: string, accessor: string, context: array<string, mixed>} $hook
      * @param class-string|null                                                                                                                        $className

src/Symfony/Component/SerDes/Tests/Context/SerializeContextTest.php

@@ -24,7 +24,6 @@ public function testWithers()
             ->withForceGenerateTemplate()
             ->withType('TYPE')
             ->withJsonEncodeFlags(123)
-            ->withUnionSelector(['int|string' => 'int'])
             ->withObjectHook($hook)
             ->withObjectHook($hook, 'className')
             ->withPropertyHook($hook)
@@ -40,7 +39,6 @@ public function testWithers()
                     'className::$propertyName' => $hook,
                 ],
             ],
-            'union_selector' => ['int|string' => 'int'],
             'json_encode_flags' => 123,
             'type' => 'TYPE',
             'force_generate_template' => true,