fix: update deprecated notificationConfig in healthcare API

Author: noerog

healthcare/fhir/patchFhirStore.js

@@ -40,9 +40,9 @@ const main = (
     const name = `projects/${projectId}/locations/${cloudRegion}/datasets/${datasetId}/fhirStores/${fhirStoreId}`;
     const request = {
       name,
-      updateMask: 'notificationConfig',
+      updateMask: 'notificationConfigs',
       resource: {
-        notificationConfig: {
+        notificationConfigs: {
           pubsubTopic: `projects/${projectId}/topics/${pubsubTopic}`,
         },
       },