Normalize updated closure string representation in PHP 8.4

tests/php/src/DevTools/CallbackReflectionTest.php

@@ -242,7 +242,15 @@ public function test_get_source( $function, $source_function, $name, $type, $fil
 		$this->assertEquals( $name, $source['name'] );
 		$this->assertEquals( $file, $source['file'] );
 		$this->assertTrue( is_int( $source['line'] ) );
-		$this->assertEquals( $source_function, $source['function'] );
+		$this->assertEquals(
+			$source_function,
+			// In PHP 8.4, a closure's string representation changes from {closure} to {closure:Test_AMP_Validation_Manager::test_decorate_shortcode_and_filter_source():1831}. So this is normalized here.
+			preg_replace(
+				'/{closure:[^}]+}/',
+				'{closure}',
+				$source['function']
+			)
+		);
 		/** @var ReflectionFunction $reflection */
 		$reflection = $source['reflection'];
 		$this->assertInstanceOf( $reflection_class, $reflection );

tests/php/validation/test-class-amp-validation-manager.php

@@ -2016,6 +2016,13 @@ public function test_decorate_shortcode_and_filter_source() {
 			]
 		);
 
+		// In PHP 8.4, a closure's string representation changes from {closure} to {closure:Test_AMP_Validation_Manager::test_decorate_shortcode_and_filter_source():1831}. So this is normalized here.
+		$filtered_content = preg_replace(
+			'/{closure:[^}]+}/',
+			'{closure}',
+			$filtered_content
+		);
+
 		$this->assertEquals(
 			preg_split( '/(?=<)/', $expected_content ),
 			preg_split( '/(?=<)/', $filtered_content )