minor #12748 *Response::create() method is deprecated (OskarStark)

This PR was merged into the 4.3 branch.

Discussion
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*Response::create() method is deprecated

@fabpot deprecated `*Response::create()` methods in symfony/symfony#34771

I think we can use `__construct` from the lowest version on (no occurences in `3.4`, so `4.3`) from now!
No need to mention the deprecation itself in the docs IMHO

Thats why I target `4.3`

Commits
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e930ea9 *Response::create() method is deprecated

Author: OskarStark

migration.rst

@@ -433,7 +433,7 @@ which script to call and wrap the output in a response class::
     {
         public function loadLegacyScript(string $requestPath, string $legacyScript)
         {
-            return StreamedResponse::create(
+            return new StreamedResponse(
                 function () use ($requestPath, $legacyScript) {
                     $_SERVER['PHP_SELF'] = $requestPath;
                     $_SERVER['SCRIPT_NAME'] = $requestPath;