i18n: restore key parity after the Hebrew locale

The translation parity test fails on main since the Hebrew locale
landed. Three gaps, all from catalogs drifting past each other:

The new he locale was based on an older en catalog and was missing 17
keys (pin/unpin, recipient autocomplete, attachment-upload validation,
the date_locale block, the tint_list_rows and show_folder_total_count
settings, language.sk). They are translated to Hebrew here; date_locale
keeps the same English values every other locale currently has.

The rtl_editing setting existed only in en and he - added translated to
the other 20 locales.

language.he was missing everywhere - added as the endonym "עברית" to
all locales, matching how the other language names are written.

locales/nl/common.json

@@ -809,6 +809,7 @@
     "nl": "Nederlands",
     "pl": "Polski",
     "pt": "Português",
+    "he": "עברית",
     "ru": "Русский",
     "sk": "Slovenčina",
     "uk": "Українська",
@@ -1274,6 +1275,10 @@
       "return_to_list_after_action": {
         "label": "Terug naar lijst na verwijderen of markeren als ongelezen",
         "description": "Na het verwijderen of als ongelezen markeren van het geopende bericht terugkeren naar de berichtenlijst in plaats van het volgende bericht te openen."
+      },
+      "rtl_editing": {
+        "label": "Ondersteuning voor rechts-naar-links bewerken",
+        "description": "Voegt een richtingsknop toe aan de werkbalk van de editor waarmee alinea's links-naar-rechts of rechts-naar-links kunnen worden ingesteld"
       }
     },
     "composer": {