minor symfony#23458 [HttpKernel] fix DumpDataCollector tests (xabbuh)

This PR was merged into the 3.2 branch.

Discussion
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[HttpKernel] fix DumpDataCollector tests

| Q             | A
| ------------- | ---
| Branch?       | 3.2
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets |
| License       | MIT
| Doc PR        |

to reflect the changes from symfony#23413

Commits
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5dbee5b [HttpKernel] fix DumpDataCollector tests

Author: nicolas-grekas

src/Symfony/Component/HttpKernel/Tests/DataCollector/DumpDataCollectorTest.php

@@ -50,7 +50,7 @@ public function testDump()
         );
         $this->assertEquals($xDump, $dump);
 
-        $this->assertStringMatchesFormat('a:3:{i:0;a:5:{s:4:"data";O:39:"Symfony\Component\VarDumper\Cloner\Data":%a', $collector->serialize());
+        $this->assertStringMatchesFormat('a:3:{i:0;a:5:{s:4:"data";%c:39:"Symfony\Component\VarDumper\Cloner\Data":%a', $collector->serialize());
         $this->assertSame(0, $collector->getDumpsCount());
         $this->assertSame('a:2:{i:0;b:0;i:1;s:5:"UTF-8";}', $collector->serialize());
     }