Tests: Correct PHPUnit version requirement in tests using ::createPartialMock().

The method was introduced in PHPUnit 5.5, not 6.0.

Follow-up to [48945], [48947] [51226].

See #52625.

git-svn-id: https://develop.svn.wordpress.org/trunk@51234 602fd350-edb4-49c9-b593-d223f7449a82

Author: SergeyBiryukov

tests/phpunit/tests/rest-api/rest-request.php

@@ -1008,7 +1008,7 @@ public function test_set_param_with_invalid_json() {
 
 	/**
 	 * @ticket 51255
-	 * @requires PHPUnit >= 6
+	 * @requires PHPUnit >= 5.5
 	 */
 	public function test_route_level_validate_callback() {
 		$request = new WP_REST_Request();
@@ -1033,7 +1033,7 @@ public function test_route_level_validate_callback() {
 
 	/**
 	 * @ticket 51255
-	 * @requires PHPUnit >= 6
+	 * @requires PHPUnit >= 5.5
 	 */
 	public function test_route_level_validate_callback_no_parameter_callbacks() {
 		$request = new WP_REST_Request();
@@ -1053,7 +1053,7 @@ public function test_route_level_validate_callback_no_parameter_callbacks() {
 
 	/**
 	 * @ticket 51255
-	 * @requires PHPUnit >= 6
+	 * @requires PHPUnit >= 5.5
 	 */
 	public function test_route_level_validate_callback_is_not_executed_if_parameter_validation_fails() {
 		$request = new WP_REST_Request();

tests/phpunit/tests/rest-api/rest-server.php

@@ -1571,7 +1571,7 @@ public function test_invalid_handler() {
 
 	/**
 	 * @ticket 50244
-	 * @requires PHPUnit >= 6
+	 * @requires PHPUnit >= 5.5
 	 */
 	public function test_callbacks_are_not_executed_if_request_validation_fails() {
 		$callback = $this->createPartialMock( 'stdClass', array( '__invoke' ) );