Get pull requests changes
        :param project:
        :param repository:
        :param pull_request_id: the ID of the pull request within the repository
        :return:

def get_pull_requests_changes(self, project, repository, pull_request_id):
        """
        Get pull requests changes
        :param project:
        :param repository:
        :param pull_request_id: the ID of the pull request within the repository
        :return:
        """
        url = 'rest/api/1.0/projects/{project}/repos/{repository}/pull-requests/{pullRequestId}/changes'.format(
            project=project,
            repository=repository,
            pullRequestId=pull_request_id)
        params = {'start': 0}
        response = self.get(url, params=params)
        if 'values' not in response:
            return []
        changes_list = (response or {}).get('values')
        while not response.get('isLastPage'):
            params['start'] = response.get('nextPageStart')
            if params['start'] is None:
                log.warning('Too many changes in pull request. Changes list is incomplete.')
                break
            response = self.get(url, params=params)
            changes_list += (response or {}).get('values')
        return changes_list