String freeze exception request for Spectacle MR 308

[Noah Davis]

https://invent.kde.org/graphics/spectacle/-/merge_requests/308

Almost exactly the same, except I removed the beginning of an HTML tag
from the string.

Old string: "You can use the following placeholders in the filename,
which will be replaced with actual text when the file is
saved:<blockquote>"

New string: "You can use the following placeholders in the filename,
which will be replaced with actual text when the file is saved:"