[1.6.x] Fixed #21440 -- Typo in topics/http/shortcuts.txt

Thanks olof.bjarnason at gmail.com for the report.

Backport of 6e9e6ca071 from master
[1.6.x] Fixed #21415 -- Replaced escape sequence by literal non-breaking space

Unfortunately, escape sequences (\x.. or \u....) do not fit well
with the gettext toolchain. Falling back to using literal char,
even if visibility is not ideal.

Backport of 7e0ebd74c from master.
[1.6.x] Updated humanize translation catalog

Refs #21415
[1.6.x] Fixed #21440 -- Typo #2 in topics/http/shortcuts.txt

Thanks alasdair.

Backport of d011714002 from master