Refactor translation and implement better interpolation

In addition to this, let's also refactor to utilize better interpolation per > https://docs.gitlab.com/ee/development/i18n/externalization.html#interpolation

The following discussion from !47976 (merged) should be addressed:

• @mlunoe started a discussion: (+1 comment)

  Suggestion: Since we are now adding translations for these, should we go through the effort of also adding them to a particular scope?