docs: Improve help text about site vs. WordPress URL settings

[tobifjellner]

Hi,
I'm looking at ​https://build.trac.wordpress.org/browser/trunk/wp-admin/options-general.php?marks=30#L30
and thinking about how to improve the help string:
"The WordPress URL and the Site URL can be the same (example.com) or different; for example, having the WordPress core files (example.com/wordpress) in a subdirectory instead of the root directory."

1. Since the URL's should include http/https, I believe the sample should also have that: "​https://example.com)
2. It would be good to elaborate a bit more on the difference between these two URL's. What about "WordPress URL is where the core files of WordPress are installed. Site URL is the URL a visitor enters in their browser in order to reach your site."

• Perhaps we should also mention here about http/https specifically?
• What about: Remember that if you want to move your site to a different domain, you'll usually need to first configure this outside of WordPress.

[SergeyBiryukov]

This appears to be a duplicate of #50886, which got some more traction.