MDL-83617 gradereport_grader: fix encoding url

When changing the number of grades per page, the redirect url was encoded twice.

grade/report/grader/index.php

@@ -204,7 +204,7 @@
 }
 
 $perpagedata = [
-    'baseurl' => new moodle_url('/grade/report/grader/index.php', ['id' => s($courseid), 'report' => 'grader']),
+    'baseurl' => (new moodle_url('/grade/report/grader/index.php', ['id' => s($courseid), 'report' => 'grader']))->out(false),
     'options' => []
 ];
 foreach ($pagingoptions as $key => $name) {

grade/report/grader/templates/perpage.mustache

@@ -43,7 +43,7 @@
 </label>
 {{#js}}
     document.getElementById('{{uniqid}}').addEventListener('change', function(e) {
-        var url = new URL('{{baseurl}}');
+        var url = new URL('{{{baseurl}}}');
         url.searchParams.set('perpage', e.target.value);
 
         window.location.href = url;

grade/report/grader/tests/behat/pagination.feature

@@ -67,6 +67,7 @@ Feature: grader report pagination
     Then I should see "103" node occurrences of type "tr" in the "user-grades" "table"
     And I should see "2" in the ".stickyfooter .pagination" "css_element"
     And I should not see "3" in the ".stickyfooter .pagination" "css_element"
+    And the url should match "/grade/report/grader/index\.php\?id=[0-9]+&report=grader&perpage=100$"
 
   @javascript
   Scenario: The pagination bar is only displayed when there is more than one page

lib/tests/behat/behat_general.php

@@ -99,6 +99,25 @@ public function i_am_on_course_index() {
         $this->execute('behat_general::i_visit', ['/course/index.php']);
     }
 
+    /**
+     * Checks, that current page PATH matches regular expression
+     *
+     * Example: Then the url should match "/course/index\.php"
+     * Example: Then the url should match "/mod/forum/view\.php\?id=[0-9]+"
+     * Example: And the url should match "^http://moodle\.org"
+     *
+     * @Then /^the url should match (?P<pattern>"(?:[^"]|\\")*")$/
+     */
+    public function the_url_should_match($pattern) {
+        $url = $this->getSession()->getCurrentUrl();
+
+        if (preg_match($pattern, $url) === 1) {
+            return;
+        }
+
+        throw new ExpectationException(sprintf('The url "%s" should match with %s', $url, $pattern), $this->getSession());
+    }
+
     /**
      * Reloads the current page.
      *