Strip extra trailing new lines

[jayvdb]

In #4, we kept the trailing blank line, which is good ..

but, it would be nice if after all operations, before the file is written, a final modification is made to ensure there is only one single trailing line feed.
i.e. no blank lines.

Otherwise, we need to remove trailing blank lines like https://github.com/moremoban/setupmobans/blob/78bcfbc/templates/gitignore.jj2#L99

[chfw]

The right number of Blank lines helps reading. Are you sure that you won't read the files yourself?

[chfw]

I misunderstood your requirement but it is done now.