minor #16663 [Debug] remove unused use statement (Tobion)

This PR was merged into the 3.0-dev branch.

Discussion
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[Debug] remove unused use statement

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

ref #15418

Commits
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a862e5e [Debug] remove unused use statement

src/Symfony/Component/Debug/ExceptionHandler.php

@@ -11,7 +11,6 @@
 
 namespace Symfony\Component\Debug;
 
-use Symfony\Component\HttpFoundation\Response;
 use Symfony\Component\Debug\Exception\FlattenException;
 use Symfony\Component\Debug\Exception\OutOfMemoryException;
 

src/Symfony/Component/Debug/README.md

@@ -31,7 +31,7 @@ Note that the `Debug::enable()` call also registers the debug class loader
 from the Symfony ClassLoader component when available.
 
 This component can optionally take advantage of the features of the HttpKernel
-and HttpFoundation components.
+component.
 
 Resources
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