Normalize whitespace in source files

Ensure that no source files have trailing whitespace at end of lines and ensure that all files end with a single trailing newline.

This also adds Github Actions to enforce whitespace conventions.

src-ui/src/app/components/document-detail/metadata-collapse/metadata-collapse.component.html

@@ -20,4 +20,4 @@
           </tr>
       </tbody>
   </table>
-</div>
+</div>

src-ui/src/app/components/document-detail/metadata-collapse/metadata-collapse.component.scss

@@ -1,3 +1,3 @@
 .metadata-column {
   overflow-wrap: anywhere;
-}
+}