[ENG-8177] Institution dashboard not showing user affiliations for Projects, Registrations and Preprints tabs (#11276)

* display only institution-specific user metrics reports

* add missing exlude statement

Author: antkryt

api/institutions/views.py

@@ -585,13 +585,17 @@ class _NewInstitutionUserMetricsList(InstitutionMixin, ElasticsearchListView):
     ))
 
     def get_default_search(self):
-        _yearmonth = InstitutionalUserReport.most_recent_yearmonth()
-        if _yearmonth is None:
+        base_search = InstitutionalUserReport.search().filter(
+            'term',
+            institution_id=self.get_institution()._id,
+        )
+        yearmonth = InstitutionalUserReport.most_recent_yearmonth(base_search=base_search)
+        if yearmonth is None:
             return None
+
         return (
-            InstitutionalUserReport.search()
-            .filter('term', report_yearmonth=str(_yearmonth))
-            .filter('term', institution_id=self.get_institution()._id)
+            base_search
+            .filter('term', report_yearmonth=str(yearmonth))
             .exclude('term', user_name='Deleted user')
         )