make qualifiers translatable

[Natkeeran]

GitHub Issue: (link)
The EDTF Field formatter terms such as uncertain and approximate are currently cannot be translated via Drupal UI.

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  Release pull requests, etc.)

What does this Pull Request do?

This PR makes the qualifier terms related to EDTF Field formatter translatable.

What's new?

Makes the qualifier terms as translatable variables.

How should this be tested?

• Add a language to the Drupal (admin/config/regional/language) if it only has one language. Also enable User interface translation.
• Create repository items with values such as 2000~, 2000?, 2000-01~, 2000-01?, 2000-01-22~, 2000-01-22? in the source language
• Switch the language, the qualifier terms such as approximate and uncertain will be in the source language
• Pull the PR, cache clear
• Go to the target language. This will register the terms that need to be translated.
• Go to User interface translation (admin/config/regional/translate), search for the term, and provide the translated terms.
• Go back to the item in the target language. It should show the translated field formatter label.
• Alternatively, you can export the po file containing the current translation ids and strings and add the required translations (year, month, day, uncertain, approximate)

Additional Notes:

Any additional information that you think would be helpful when reviewing this
PR.

Interested parties

Tag (@ mention) interested parties or, if unsure, @Islandora/committers

[seth-shaw-asu]

This is great, @Natkeeran. Thanks!