Merge branch '3.4' into 4.3

* 3.4:
  #30432 fix an error message
  fix paths to detect code owners
  [Validator] Ensure numeric subpaths do not cause errors on PHP 7.4
  Remove unused local variables in tests
  Make sure to collect child forms created on *_SET_DATA events
  do not render errors for checkboxes twice

Author: nicolas-grekas

Tests/Command/LintCommandTest.php

@@ -97,7 +97,7 @@ public function testLintFileNotReadable()
         $filename = $this->createFile('');
         unlink($filename);
 
-        $ret = $tester->execute(['filename' => $filename], ['decorated' => false]);
+        $tester->execute(['filename' => $filename], ['decorated' => false]);
     }
 
     /**

Tests/ParserTest.php

@@ -64,7 +64,7 @@ public function testTabsInYaml()
 
         foreach ($yamls as $yaml) {
             try {
-                $content = $this->parser->parse($yaml);
+                $this->parser->parse($yaml);
 
                 $this->fail('YAML files must not contain tabs');
             } catch (\Exception $e) {