bug symfony#59404 [Mailer] Fix SMTP stream EOF handling on Windows by using feof() (skmedix)

This PR was merged into the 6.4 branch.

Discussion
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[Mailer] Fix SMTP stream EOF handling on Windows by using feof()

| Q             | A
| ------------- | ---
| Branch?       | 6.4
| Bug fix?      | yes
| New feature?  | no <!-- please update src/**/CHANGELOG.md files -->
| Deprecations? | no <!-- please update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Issues        | Fix symfony#59351
| License       | MIT

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Full explanation of this change here: symfony#59351 (comment)
Help with tests would be appreciated.

Commits
-------

ed18c7c [Mailer] Fix SMTP stream EOF handling on Windows by using feof()

Author: nicolas-grekas

src/Symfony/Component/Mailer/Transport/Smtp/Stream/AbstractStream.php

@@ -80,11 +80,10 @@ public function readLine(): string
 
         $line = @fgets($this->out);
         if ('' === $line || false === $line) {
-            $metas = stream_get_meta_data($this->out);
-            if ($metas['timed_out']) {
+            if (stream_get_meta_data($this->out)['timed_out']) {
                 throw new TransportException(sprintf('Connection to "%s" timed out.', $this->getReadConnectionDescription()));
             }
-            if ($metas['eof']) {
+            if (feof($this->out)) { // don't use "eof" metadata, it's not accurate on Windows
                 throw new TransportException(sprintf('Connection to "%s" has been closed unexpectedly.', $this->getReadConnectionDescription()));
             }
             if (false === $line) {