Translate descriptions for declarative_enum dynamically

What does this MR do and why?

Translate descriptions for declarative_enum dynamically using N_(...) combined with _(var).

Prior this change the translated strings were loaded in class scope so switching the locale had no effect on them anymore. The descriptions were always displayed in English.

This is a follow-up of !55525 (merged) and !58431 (merged).

Related to #326765 (closed).

How to set up and validate locally

View vulnerabilities page with locale zh_CN and see dismissal reason translated properly.

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