Update metrics.md

Add isTime == true param to Trends

Author: dirtydiesel46

docs/sources/v0.47.x/using-k6-browser/metrics.md

@@ -124,7 +124,7 @@ export const options = {
   },
 };
 
-const myTrend = new Trend('total_action_time');
+const myTrend = new Trend('total_action_time',true);
 
 export default async function () {
   const page = browser.newPage();
@@ -166,5 +166,5 @@ After you run the test, you should see a similar output as the one below.
 ```bash
   iteration_duration..........: avg=1.06s    min=1.06s    med=1.06s    max=1.06s    p(90)=1.06s    p(95)=1.06s
   iterations..................: 1      0.70866/s
-  total_action_time.............: avg=295.3    min=295.3    med=295.3    max=295.3    p(90)=295.3    p(95)=295.3
-```
+  total_action_time.............: avg=295.3s    min=295.3s    med=295.3s    max=295.3s    p(90)=295.3s    p(95)=295.3s
+```