feat: Translate frontend/src/i18n/en.json in bg

74% of minimum 50% translated source file: 'frontend/src/i18n/en.json'
on 'bg'.

Sync of partially translated files: 
untranslated content is included with an empty translation 
or source language content depending on file format

frontend/src/i18n/bg.json

@@ -197,8 +197,8 @@
     "hideDotfiles": "Скрий фаловете започващи с точка",
     "insertPath": "Вмъкни пътя",
     "insertRegex": "Вмъкни регулярен израз",
-    "instanceName": "Instance name",
-    "language": "Language",
+    "instanceName": "Име на инстанцията",
+    "language": "Език",
     "lockPassword": "Prevent the user from changing the password",
     "newPassword": "Your new password",
     "newPasswordConfirm": "Confirm your new password",