Fix issue when recordType not recognized in NYPL-Core

Currently, if the indexed recordTypeId is not recognized in NYPL-core,
serialization fails, affecting search and bib endpoints. Additionally,
it's possible for the recordType aggregation to be served without a label.
This change ensures that invalid recordTypes are removed from both bib
serialization and aggs. In general we should strive to keep indexed recordTypes
aligned with NYPL-Core; This update handles the case where they're not.

lib/jsonld_serializers.js

@@ -287,9 +287,11 @@ class ResourceSerializer extends JsonLdItemSerializer {
 }
 
 ResourceSerializer.getFormattedRecordType = function (recordTypeId) {
+  const prefLabel = recordTypes[recordTypeId]?.label
+  if (!prefLabel) return null
   return {
     '@id': recordTypeId,
-    prefLabel: recordTypes[recordTypeId].label
+    prefLabel
   }
 }
 
@@ -501,12 +503,16 @@ class AggregationSerializer extends JsonLdItemSerializer {
         } else if (field === 'recordType') {
           // Build recordType agg labels from nypl-core:
           v.label = recordTypes[v.value]?.label
+          // Unknown recordType? Remove it:
+          if (!v.label) return null
         } else {
           v.label = v.value
         }
 
         return v
       })
+        // Remove null aggregations (removed because found to be invalid)
+        .filter((agg) => agg)
     } catch (e) { console.error(e) }
 
     // Now that we've formatted buckets (into `values` prop), delete `buckets`