In tests/examples/wibox/widget/textbox/line_spacing.lua, there is a typo
It's supposed to be "has", but it's "shas", this is obviously not a grammar issue, so it's a typo.
The list of possible values was missing one. Additionally, this adds an
example to visualize the available options.
Signed-off-by: Lucas Schwiderski <lucas@lschwiderski.de>