BLD: added newline for all json nominee files

[lacabra]

This pull request adds a newline to each JSON nominee file. The rationale is that given that JSON files are text files, which are defined as (see this answer from unix.stackexchange):

A text file, under unix, consists of a series of lines, each of which ends with a newline character (\n). A file that is not empty and does not end with a newline is therefore not a text file.

*nix systems expect text files to be ended with an empty newline, otherwise some text-file-processing utilities and applications will break if this is not followed. This PR ensures that all JSON files will be properly treated as text files.

This PR does the following:

• Modified the scripts that the CI runs to allow for newlines at the end of JSON files
• Actually modifying all JSON files in the repo adding a newline at the end