help: correct search instructions for missing fields (review suggestions)

Co-authored-by: Guillaume Viger <[email protected]>

Author: tmorrell

invenio_app_rdm/theme/templates/semantic-ui/invenio_app_rdm/help/search.en.html

@@ -188,9 +188,9 @@ <h3>Missing values</h3>
   </p>
   <p>
     <strong>Example:</strong>
-    <a href="/search?page=1&amp;size=20&amp;q=NOT%20_exists_:metadata.additional_titles"
-      ><code>NOT _exists_:metadata.additional_titles</code></a
-    >
+    <a href="/search?page=1&amp;size=20&amp;q=NOT%20_exists_:metadata.additional_titles">
+      <code>NOT _exists_:metadata.additional_titles</code>
+    </a>
     (all records without metadata.additional_titles)
   </p>
   <p>

invenio_app_rdm/theme/templates/semantic-ui/invenio_app_rdm/help/search.sv.html

@@ -180,9 +180,9 @@ <h3>Fält som saknar värden</h3>
   </p>
   <p>
     <strong>Exempel:</strong>
-    <a href="/search?page=1&amp;size=20&amp;q=NOT%20_exists_:metadata.additional_titles"
-      ><code>NOT _exists_:metadata.additional_titles</code></a
-    >
+    <a href="/search?page=1&amp;size=20&amp;q=NOT%20_exists_:metadata.additional_titles">
+      <code>NOT _exists_:metadata.additional_titles</code>
+    </a>
     (alla poster utan metadata.additional_titles)
   </p>
   <p>