Add CHANGELOG and docstring

Signed-off-by: Tushar Goel <[email protected]>

Author: TG1999

vulnerabilities/models.py

@@ -219,6 +219,10 @@ def with_vulnerability_counts(self):
 
 
 def get_purl_query_lookups(purl):
+    """
+    Do not reference all the possible qualifiers and relax the
+    purl matching to only lookup the type, namespace, name and version fields.
+    """
     lookup_fields = ["type", "namespace", "name", "version"]
     return {
         field_name: value