Exact patient no. in filters (#2136)

exact patient no for search

care/facility/api/viewsets/patient.py

@@ -109,7 +109,7 @@ class PatientFilterSet(filters.FilterSet):
     allow_transfer = filters.BooleanFilter(field_name="allow_transfer")
     name = filters.CharFilter(field_name="name", lookup_expr="icontains")
     patient_no = filters.CharFilter(
-        field_name="last_consultation__patient_no", lookup_expr="icontains"
+        field_name="last_consultation__patient_no", lookup_expr="iexact"
     )
     gender = filters.NumberFilter(field_name="gender")
     age = filters.NumberFilter(field_name="age")