use systemBlue directly

deltachat-ios/Extensions/UIColor+Extensions.swift

@@ -25,8 +25,6 @@
 import Foundation
 import UIKit
 
-// swiftlint:disable explicit_acl
-
 internal extension UIColor {
 
     // Defaults used in messageKit, not in active use
@@ -35,9 +33,4 @@ internal extension UIColor {
     static let inputBarGray = UIColor(red: 247/255, green: 247/255, blue: 247/255, alpha: 1.0)
     static let playButtonLightGray = UIColor(red: 230/255, green: 230/255, blue: 230/255, alpha: 1.0)
     static let sendButtonBlue = UIColor(red: 15/255, green: 135/255, blue: 255/255, alpha: 1.0)
-
-    static var systemBlue: UIColor {
-        return UIButton(type: .system).tintColor
-    }
-    
 }