Fix placeholders names used in 'core.forum.security.token_item_title' translation

[rob006]

See

framework/framework/core/locale/core.yml

Line 505 in da651c7

token_item_title: "{title} - {token}"

Without this change token title always contains only -.

Necessity

• Has the problem that is being solved here been clearly explained?
• If applicable, have various options for solving this problem been considered?
• For core PRs, does this need to be in core, or could it be in an extension?
• Are we willing to maintain this for years / potentially forever?

Confirmed

• Frontend changes: tested on a local Flarum installation.
• Backend changes: tests are green (run composer test).
• Core developer confirmed locally this works as intended.
• Tests have been added, or are not appropriate here.