Removes the namespacing from security strings

What does this MR do?

Removes the i18n namespacing from a lot of the security strings. This was brought up in #37912 (closed) and helps out with translations of common phrases such as, 'create issue', and 'more info'.

We may potentially need to move over a couple of translated strings, but I'm not 100% sure how to do that. I may have also been slightly heavy-handed in this endeavour so please feel free to reign me back in where required.

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• [-] Separation of EE specific content