Alternate title: _Applying #6684-similar fix to stroke_
#6684 makes sure the "current" transformation, at the moment of filling radial gradients is the `baseTransform` (that of the rescource (page), as it says in the specs). However, this should also be fixed in [`CanvasGraphics_stroke`](https://github.com/dsprenkels/pdf.js/blob/a9081653fc565eb72c3eb5142c17088cb162e7ce/src/display/canvas.js#L1052).

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