Fix merge authors feature

[luistoptal]

User story

Merge author feature should work as expected

Example:

http://gigadb.gigasciencejournal.com:9170/adminAuthor/update/id/14

Acceptance criteria

• Navigate to an author update page, e.g. http://gigadb.gigasciencejournal.com:9170/adminAuthor/update/id/14
• Click on merge author
• Click on any author to open merge modal
• Click on "yes, merge authors"
• Authors shoudl be merged

Additional Info

I believe the source of the issue is file protected/views/adminAuthor/admin.php, line with: echo 'origin_graph = ' . CJSON::encode($origin_author->getIdenticalAuthors()) . ';';

It looks like expression CJSON::encode($origin_author->getIdenticalAuthors()) is always evaluating to false even though something else would be expected. This looks more like a backend issue

[luistoptal]

@rija This issue takes place in the develop branch. It makes it impossible to merge authors. It's more of a backend issue, I believe