Problem Description

Exporting a collection in JSON produces an invalid .json file: documents are not separated with commas and are not in an array

Steps to Reproduce

1. Connect to any non-empty database
2. Open any non-empty collection
3. Click 'Collection/Export Collection' in the top menu
4. Select 'JSON' as the 'Output File Type'
5. Click 'Browse' and specify any name of the file matching the *.json pattern
6. Click 'Export'
7. Open an exported file

Expected Results

A valid JSON file is produced: documents are in an array and are separated with commas

Actual Results

An invalid JSON file is produced: documents are not in an array and are not separated with commas