[GNC-dev] Sample Report with Examples

[flywire]

https://lists.gnucash.org/pipermail/gnucash-devel/2021-September/045939.html
> The code would be easier to follow if different strings other than Hello,
World! were used, making it clearer what they relate to. While this report
might have developed from a Hello World example, a minimal program to
generate output, it's much more than that now. Can it be renamed? Maybe
just hello.scm or move it to welcome-to-gnucash.scm with a related document
title.
>
> If there are no concerns I'll put up a PR.

I made minimal changes for the strings and pushed
https://github.com/Gnucash/gnucash/pull/1501

Other changes would need a bit of discussion as would affect the docs.