Merge branch '5.4' into 6.2

* 5.4:
  [Translation][Mailer] Convert `$this` calls to static ones in data providers
  [BC Break] Make data providers for abstract test cases static
  use TestCase suffix for abstract tests in Tests directories
  Fix Request locale property doc types
  Bump absolute lowest dep to 4.4

Test/TransportFactoryTestCase.php

@@ -31,33 +31,33 @@ abstract public function createFactory(): TransportFactoryInterface;
     /**
      * @return iterable<array{0: bool, 1: string}>
      */
-    abstract public function supportsProvider(): iterable;
+    abstract public static function supportsProvider(): iterable;
 
     /**
      * @return iterable<array{0: string, 1: string, 2: TransportInterface}>
      */
-    abstract public function createProvider(): iterable;
+    abstract public static function createProvider(): iterable;
 
     /**
      * @return iterable<array{0: string, 1: string|null}>
      */
-    public function unsupportedSchemeProvider(): iterable
+    public static function unsupportedSchemeProvider(): iterable
     {
         return [];
     }
 
     /**
      * @return iterable<array{0: string, 1: string|null}>
      */
-    public function incompleteDsnProvider(): iterable
+    public static function incompleteDsnProvider(): iterable
     {
         return [];
     }
 
     /**
      * @return iterable<array{0: string, 1: string|null}>
      */
-    public function missingRequiredOptionProvider(): iterable
+    public static function missingRequiredOptionProvider(): iterable
     {
         return [];
     }