Change category selector translations

[Gnito]

This passes categoryLevel as an argument to category pickers on EditListingDetailsPanel. More freedom to choose copy-texts and smaller asset file. With this setup it's possible to adjust the copy on each level if needed.

Translation changes:

  "EditListingDetailsForm.categoryLabel": "{categoryLevel, select, categoryLevel1 {Category} other {Subcategory}}",
  "EditListingDetailsForm.categoryPlaceholder": "{categoryLevel, select, categoryLevel1 {Select category} other {Select subcategory}}",
  "EditListingDetailsForm.categoryRequired": "{categoryLevel, select, categoryLevel1 {You need to select a category.} other {You need to select a subcategory.}}",

Removed key:

  "EditListingDetailsForm.subCategoryLabel": "Subcategory",