Update email address for National Archives in print metadata

The `gsi` part has been removed from government email address. This now
matches the address given at
https://www.nationalarchives.gov.uk/information-management/keeping-touch/contacts/.

app/views/content_items/html_publication/_print_meta_data.html.erb

@@ -5,7 +5,7 @@
   © Crown copyright <%= @content_item.copyright_year %>
 </p>
 <p>
-  This publication is licensed under the terms of the Open Government Licence v3.0 except where otherwise stated. To view this licence, visit <a href="https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3">nationalarchives.gov.uk/doc/open-government-licence/version/3</a> or write to the Information Policy Team, The National Archives, Kew, London TW9 4DU, or email: <a href="mailto:psi@nationalarchives.gsi.gov.uk">psi@nationalarchives.gsi.gov.uk</a>.
+  This publication is licensed under the terms of the Open Government Licence v3.0 except where otherwise stated. To view this licence, visit <a href="https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3">nationalarchives.gov.uk/doc/open-government-licence/version/3</a> or write to the Information Policy Team, The National Archives, Kew, London TW9 4DU, or email: <a href="mailto:[email protected]">[email protected]</a>.
 </p>
 <p>
   Where we have identified any third party copyright information you will need to obtain permission from the copyright holders concerned.