MorphBorder constructor

MorphBorder({
  1. BorderSide side = BorderSide.none,
  2. StrokeCap strokeCap = .butt,
  3. StrokeJoin strokeJoin = .miter,
  4. double strokeMiterLimit = 4.0,
  5. double squash = 0.0,
  6. required Morph morph,
  7. required double progress,
  8. double startAngle = 0.0,
})