Fix Xcode 15 build error

Author: ilia3546

Sources/Views/WeekView.swift

@@ -95,14 +95,6 @@ public extension FastisConfig {
      */
     struct WeekView {
 
-        /**
-         Calendar which is used to get a `.shortWeekdaySymbols`
-
-         Default value — `.current`
-         */
-        @available(*, unavailable, message: "Use FastisConfig.calendar propery instead")
-        public var calendar: Calendar = .current
-
         /**
          Background color of the view