remove PUBMED URL redirects that match DOI or PMC (#3316)

Template.php

@@ -1626,6 +1626,14 @@ public function get_identifiers_from_url(?string $url_sent = NULL) : bool {
         if ($this->wikiname() === 'cite web') $this->change_name_to('cite journal');
         return $this->add_if_new('pmid', $match[1]);
 
+      } elseif (preg_match('~^ncbi\.nlm\.nih\.gov/entrez/eutils/elink.fcgi\?.+tool=sumsearch\.org.+id=(\d+)$~', $url, $match)) {
+        if ($url_sent) return FALSE;   // Many do not work
+        if ($this->blank(['doi', 'pmc'])) return FALSE;  // This is a redirect to the publisher, not pubmed
+        if ($match[1] == $this->get('pmc') || $match[1] == $this->get('pmid')) {
+           $this->forget($url_type);
+        }
+        return FALSE;
+
       } elseif (preg_match("~^https?://(?:www\.|)amazon(?P<domain>\.[\w\.]{1,7})/.*dp/(?P<id>\d+X?)~i", $url, $match)) {
 
         if ($this->wikiname() === 'cite web') $this->change_name_to('cite book');