minor symfony#52334 [Yaml] Inline::parse(null) not allowed (GromNaN)

This PR was merged into the 6.4 branch.

Discussion
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[Yaml]  `Inline::parse(null)` not allowed

| Q             | A
| ------------- | ---
| Branch?       | 6.4
| Bug fix?      | no
| New feature?  | no
| Deprecations? | no
| Issues        | Fix symfony#52326
| License       | MIT

It's only called with string values in the Yaml component.

This class is internal. It allows to change the arg type.
The arg type was documented as `string`.
symfony@7b1715b#diff-1d97fcfb29e99f0200c3952e9a1a11c4b9f825c0f5ad4d4515b9b1805f8c988eR47

Commits
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834e0ab Passing null to Inline::parse is not allowed

Author: fabpot

src/Symfony/Component/Yaml/Inline.php

@@ -55,7 +55,7 @@ public static function initialize(int $flags, int $parsedLineNumber = null, stri
      *
      * @throws ParseException
      */
-    public static function parse(string $value = null, int $flags = 0, array &$references = []): mixed
+    public static function parse(string $value, int $flags = 0, array &$references = []): mixed
     {
         if (null === $value) {
             return '';

src/Symfony/Component/Yaml/Tests/InlineTest.php

@@ -29,7 +29,7 @@ protected function setUp(): void
     /**
      * @dataProvider getTestsForParse
      */
-    public function testParse($yaml, $value, $flags = 0)
+    public function testParse(string $yaml, $value, $flags = 0)
     {
         $this->assertSame($value, Inline::parse($yaml, $flags), sprintf('::parse() converts an inline YAML to a PHP structure (%s)', $yaml));
     }