#180 - New metric for rolling 12 months active users

+ Update docs

Author: dustinhuynh

tests/tool_cloudmetrics_users_test.php

@@ -39,7 +39,7 @@ protected function setUp(): void {
         parent::setUp();
         $this->resetAfterTest();
     }
-    /**@var integer Second in a day */
+    /** @var integer Seconds in a day. */
     public const SECOND_IN_DAY = 86400;
 
     /** @var array[] Sample user DB data to be used in tests. */
@@ -107,6 +107,7 @@ public function test_generate_metrics(string $metricname, int $frequency, array
      * Tests test_generate_rolling_active_users_metric() for the builtin user metrics.
      *
      * @dataProvider data_for_test_generate_rolling_active_users_metric
+     * @param string $metricname The name of the metric to be tested.
      * @param array $expected List of metric items that expect to be generated.
      * @throws \dml_exception
      */