fix: remove unused locale key

Part-of: <https://dev.funkwhale.audio/funkwhale/funkwhale/-/merge_requests/2701>

front/src/locales/ar.json

@@ -3580,7 +3580,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "إلغاء",
         "submit": "إرسال"
       },
       "header": {

front/src/locales/bn_BD.json

@@ -4591,7 +4591,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "",
         "submit": ""
       },
       "header": {

front/src/locales/ca.json

@@ -4591,7 +4591,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "Cancelar",
         "submit": "Envia"
       },
       "header": {

front/src/locales/cs.json

@@ -4591,7 +4591,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "Zrušit",
         "submit": "Odeslat"
       },
       "header": {

front/src/locales/de.json

@@ -4591,7 +4591,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "Abbrechen",
         "submit": "Abschicken"
       },
       "header": {

front/src/locales/el.json

@@ -2454,7 +2454,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "Ακύρωση",
         "submit": "Υποβολή"
       },
       "header": {

front/src/locales/en_GB.json

@@ -4591,7 +4591,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "Cancel",
         "submit": "Submit"
       },
       "header": {

front/src/locales/en_US.json

@@ -4591,7 +4591,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "Cancel",
         "submit": "Submit"
       },
       "header": {

front/src/locales/eo.json

@@ -3620,7 +3620,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "Nuligi",
         "submit": "Submeti"
       },
       "header": {

front/src/locales/es.json

@@ -3940,7 +3940,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "Cancelar",
         "submit": "Enviar"
       },
       "header": {

front/src/locales/eu.json

@@ -4591,7 +4591,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "Ezeztatu",
         "submit": "Bidali"
       },
       "header": {

front/src/locales/fr_FR.json

@@ -4591,7 +4591,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "Annuler",
         "submit": "Valider"
       },
       "header": {

front/src/locales/gl.json

@@ -4591,7 +4591,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "Cancelar",
         "submit": "Enviar"
       },
       "header": {

front/src/locales/it.json

@@ -4544,7 +4544,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "Annulla",
         "submit": "Invia"
       },
       "header": {

front/src/locales/ja_JP.json

@@ -4334,9 +4334,7 @@
       }
     },
     "ChooseInstance": {
-      "button": {
+      "button": {},
-        "cancel": "キャンセル"
-      },
       "header": {
         "chooseInstance": "インスタンスを選んでください",
         "failure": "入力されたURLにアクセスできません",

front/src/locales/kab_DZ.json

@@ -2173,7 +2173,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "Sefex",
         "submit": "Envoyer"
       }
     }

front/src/locales/ml.json

@@ -1614,7 +1614,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "റദ്ദാക്കുക",
         "submit": "സമർപ്പിക്കുക"
       }
     }

front/src/locales/nb_NO.json

@@ -3287,7 +3287,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "Avbryt",
         "submit": "Send inn"
       },
       "header": {

front/src/locales/nl.json

@@ -4590,7 +4590,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "Annuleren",
         "submit": "Indienen"
       },
       "header": {

front/src/locales/oc.json

@@ -4529,7 +4529,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "Anullar",
         "submit": "Validar"
       },
       "header": {

front/src/locales/pl.json

@@ -4489,7 +4489,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "Anuluj",
         "submit": "Prześlij"
       },
       "header": {

front/src/locales/pt_BR.json

@@ -4343,7 +4343,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "Cancelar",
         "submit": "Enviar"
       },
       "header": {

front/src/locales/pt_PT.json

@@ -3593,7 +3593,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "Cancelar",
         "submit": "Enviar"
       },
       "header": {

front/src/locales/ru.json

@@ -4591,7 +4591,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "Отмена",
         "submit": "Отправить"
       },
       "header": {

front/src/locales/sv.json

@@ -3032,7 +3032,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "Ångra",
         "submit": "Skicka in"
       },
       "header": {

front/src/locales/tr.json

@@ -1679,7 +1679,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "İptal",
         "submit": "Gönder"
       },
       "header": {

front/src/locales/zh_Hans.json

@@ -4498,7 +4498,6 @@
     },
     "ChooseInstance": {
       "button": {
-        "cancel": "取消",
         "submit": "提交"
       },
       "header": {