Sort related publications from newest to oldest in detail view

[markusjt]

Requires changes to indexing as currently indexing title and holdings in relatedPublicationsStrategy but not date.

Example of DDI-C 2.5 with distStmt/distDate:

<othrStdyMat>
  <relPubl xml:lang="en" > Rapeli, Lauri (2023) Illusion of knowledge: Is the Dunning-Kruger effect in political sophistication more widespread than before? Journal of Elections, Public Opinion and Parties. https://doi.org/10.1080/17457289.2023.2214734
    <citation>
      <titlStmt>
        <titl xml:lang="en" >Illusion of knowledge: is the Dunning-Kruger effect in political sophistication more widespread than before?</titl>
        <IDNo xml:lang="en" agency="DOI" >10.1080/17457289.2023.2214734</IDNo>
      </titlStmt>
      <distStmt>
        <distDate xml:lang="en" date="2023" ></distDate>
      </distStmt>
      <holdings xml:lang="en" URI="https://doi.org/10.1080/17457289.2023.2214734" ></holdings>
    </citation>
  </relPubl>
</othrStdyMat> 

Related to #502

[john-shepherdson]

Will require that the indices are cleared and rebuilt as part of the release process, so there will be a period when there is no content in the production instance.

Ideally the 'Website unavailable due to maintenance" page should be in place for this.