Fixed Card activity shows only 20 last entries of activities and comments, by changing limit to 500 entries.

Thanks to xet7 !

Fixes #2934

client/components/activities/activities.js

@@ -1,6 +1,6 @@
 import sanitizeXss from 'xss';
 
-const activitiesPerPage = 20;
+const activitiesPerPage = 500;
 
 BlazeComponent.extendComponent({
   onCreated() {