Pull-request diff using the CURL API returns truncated JSON response

Issue Summary

When retrieving pull-requests diff using the rest API, the JSON response is truncated for a ~400kb file.

Steps to Reproduce

1. Retrieve the pull-request diff using the REST API command as shown below:

   curl -u bitbucket672:password http://localhost:7990/rest/api/1.0/projects/DIFF/repos/diff1/pull-requests/3/diff
   

2. Truncated JSON is returned.

Expected Results

Return complete diff as shown below:

it@zenox:~/Downloads/git/672/diff1$ curl -u bitbucket672:password http://localhost:7990/rest/api/1.0/projects/DIFF/repos/diff1/pull-requests/3/diff
...
"truncated":false}],"truncated":false}],"truncated":false}],"truncated":false}

Actual Results

Returns truncated file as shown below:

it@zenox:~/Downloads/git/672/diff1$ curl -u bitbucket672:password http://localhost:7990/rest/api/1.0/projects/DIFF/repos/diff1/pull-requests/3/diff
...
"truncated":false}],"truncated":true}],"truncated":true}],"truncated":true}],"truncated":true}i

Workaround

Workaround from BSERV-5429 & BSERV-11965 not working