chore(l10n): update Italian translations

Currently translated at 98.9% (93 of 94 strings)

Translation: Fossify/Calculator
Translate-URL: https://hosted.weblate.org/projects/fossify/calculator/it/
Via: Weblate

Author: albanobattistella

app/src/main/res/values-it/strings.xml

@@ -92,4 +92,5 @@
     <string name="unit_time_week">Settimana</string>
     <string name="unit_time_year">Anno</string>
     <string name="unit_length_angstrom">Angstrom</string>
+    <string name="unit_volume_legal_cup_us">Coppa legale (US)</string>
 </resources>