Support full records without pub_date or id

Why are these changes being introduced:

* Some records don't have publication date information (which is
  expected)

Relevant ticket(s):

* https://mitlibraries.atlassian.net/browse/TIMX-108

How does this address that need:

* Adds nil protection for publication dates

Document any side effects to this change:

* After handling the publication date nil, an error occurred for
  identifier not being present. I believe this is unexpected and is a
  result of incomplete Alma mappings in dev1 at this time. Handling nils
  for identifers seemed fine to include even if the data will likely
  all include at least one identifier per record.

Author: JPrevost

app/helpers/record_helper.rb

@@ -1,6 +1,6 @@
 module RecordHelper
   def doi(metadata)
-    dois = metadata['identifiers'].select { |id| id['kind'].downcase == 'doi' }
+    dois = metadata['identifiers']&.select { |id| id['kind'].downcase == 'doi' }
     return unless dois.present?
 
     dois.first['value']

app/views/record/_record.html.erb

@@ -26,7 +26,7 @@
 
       <% else %>
 
-        <% if @record['dates'].map{|date| date if date['kind'] == 'Publication date'}.compact.present? %>
+        <% if @record['dates']&.map{|date| date if date['kind'] == 'Publication date'}&.compact.present? %>
           <span class="record-year">
             : Published <%= date_parse(publication_date(@record)) %>
           </span>

test/integration/error_resilience_test.rb

@@ -15,4 +15,15 @@ class ErrorResilienceTest < ActionDispatch::IntegrationTest
       end
     end
   end
+
+  # https://mitlibraries.atlassian.net/browse/TIMX-108
+  # https://timdex-ui-pipeline-dev.herokuapp.com/record/alma:9935254980806761
+  test 'records without publication dates display without errors' do
+    VCR.use_cassette('alma record with no publication date',
+                     allow_playback_repeats: true,
+                     match_requests_on: %i[method uri body]) do
+      get '/record/alma:9935254980806761'
+      assert_response :success
+    end
+  end
 end