feature #47730 Ban DateTime from the codebase (WebMamba)

This PR was squashed before being merged into the 6.2 branch.

Discussion
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Ban DateTime from the codebase

| Q             | A
| ------------- | ---
| Branch?       | 6.2
| Bug fix?      | no
| New feature?  | yes
| Deprecations? | yes
| Tickets       | #47580
| License       | MIT
| Doc PR        | symfony

As discuss in this issue, the purpose of this PR is to remove DateTime from the code base in favor to DateTimeImmutable. I will process it component by component. Feel free to discuss!

Commits
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689385a83f Ban DateTime from the codebase

Author: fabpot

BufferingLogger.php

@@ -53,7 +53,7 @@ public function __destruct()
                     if (null === $val || \is_scalar($val) || (\is_object($val) && \is_callable([$val, '__toString']))) {
                         $message = str_replace("{{$key}}", $val, $message);
                     } elseif ($val instanceof \DateTimeInterface) {
-                        $message = str_replace("{{$key}}", $val->format(\DateTime::RFC3339), $message);
+                        $message = str_replace("{{$key}}", $val->format(\DateTimeInterface::RFC3339), $message);
                     } elseif (\is_object($val)) {
                         $message = str_replace("{{$key}}", '[object '.get_debug_type($val).']', $message);
                     } else {
@@ -62,7 +62,7 @@ public function __destruct()
                 }
             }
 
-            error_log(sprintf('%s [%s] %s', date(\DateTime::RFC3339), $level, $message));
+            error_log(sprintf('%s [%s] %s', date(\DateTimeInterface::RFC3339), $level, $message));
         }
     }
 }