analytics-realm-activity: Add link to realm's stats page.

Adds the  pie chart icon stats page link to the realm_activity
page header.

analytics/views/realm_activity.py

@@ -13,6 +13,7 @@ from analytics.views.activity_common import (
     format_date_for_activity_reports,
     get_user_activity_summary,
     make_table,
+    realm_stats_link,
     user_activity_link,
 )
 from zerver.decorator import require_server_admin
@@ -252,8 +253,10 @@ def get_realm_activity(request: HttpRequest, realm_str: str) -> HttpResponse:
     data += [(page_title, content)]
 
     title = realm_str
+    realm_stats = realm_stats_link(realm_str)
+
     return render(
         request,
         "analytics/activity.html",
-        context=dict(data=data, realm_link=None, title=title),
+        context=dict(data=data, realm_stats_link=realm_stats, title=title),
     )

templates/analytics/activity.html

@@ -15,11 +15,8 @@
     <br />
     {% endif %}
 
-    <h4>{{ title }}</h4>
+    <h4>{{ title }} {% if realm_stats_link %}{{ realm_stats_link }}{% endif %}</h4>
 
-    {% if realm_link %}
-    <a href="{{ realm_link }}">Graph</a><br />
-    {% endif %}
 
     <ul class="nav nav-tabs">
         {% for name, activity in data %}