minor #36075 [UID] Rename NullUuid to NilUuid (ro0NL)

This PR was merged into the 5.1-dev branch.

Discussion
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[UID] Rename NullUuid to NilUuid

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Tickets       | Fix #... <!-- prefix each issue number with "Fix #", if any -->
| License       | MIT
| Doc PR        | symfony/symfony-docs#... <!-- required for new features -->
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As per https://tools.ietf.org/html/rfc4122#section-4.1.7

Commits
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cbb6d23 [UID] Rename NullUuid to NilUuid

src/Symfony/Component/Uid/NullUuid.php → src/Symfony/Component/Uid/NilUuid.php

@@ -16,7 +16,7 @@
  *
  * @author Grégoire Pineau <lyrixx@lyrixx.info>
  */
-class NullUuid extends Uuid
+class NilUuid extends Uuid
 {
     protected const TYPE = UUID_TYPE_NULL;
 

src/Symfony/Component/Uid/Tests/UuidTest.php

@@ -12,7 +12,7 @@
 namespace Symfony\Tests\Component\Uid;
 
 use PHPUnit\Framework\TestCase;
-use Symfony\Component\Uid\NullUuid;
+use Symfony\Component\Uid\NilUuid;
 use Symfony\Component\Uid\Uuid;
 use Symfony\Component\Uid\UuidV1;
 use Symfony\Component\Uid\UuidV3;
@@ -146,11 +146,11 @@ public function testCompare()
         $this->assertSame([$a, $b, $c, $d], $uuids);
     }
 
-    public function testNullUuid()
+    public function testNilUuid()
     {
         $uuid = Uuid::fromString('00000000-0000-0000-0000-000000000000');
 
-        $this->assertInstanceOf(NullUuid::class, $uuid);
+        $this->assertInstanceOf(NilUuid::class, $uuid);
         $this->assertSame('00000000-0000-0000-0000-000000000000', (string) $uuid);
     }
 }

src/Symfony/Component/Uid/Uuid.php

@@ -50,7 +50,7 @@ public static function fromString(string $uuid): self
             case UuidV4::TYPE: return new UuidV4($uuid);
             case UuidV5::TYPE: return new UuidV5($uuid);
             case UuidV6::TYPE: return new UuidV6($uuid);
-            case NullUuid::TYPE: return new NullUuid();
+            case NilUuid::TYPE: return new NilUuid();
             case self::TYPE: return new self($uuid);
         }