A Weblate translation of a <plurals> may not fill every CLDR quantity
form its locale defines — e.g. Arabic's import_reminder_prompt_body_existing
omits the "zero" form — which lint flags fatally as MissingQuantity and
aborts the CI build. The missing form falls back to "other" at runtime, so
this is the same partial-translation case we already accept for
MissingTranslation; downgrade MissingQuantity to informational alongside it.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>