Shadows are not working in SVG rendering

[francozanardi]

Description

Currently, when a image is rendered as SVG, the text and box shadows are being ignored.

Steps to reproduce

from pictex import *

canvas = (
    Canvas()
    .font_family("Poppins-Bold.ttf")
    .color("blue")
    .font_size(100)
    .text_shadows(
        Shadow((-2, 0), 0, "pink"),
        Shadow((-3, 0), 0, "pink")
    )
)

canvas.render("hello").save("shadows.png")
canvas.render_as_svg("hello").save("shadows.svg")

shadows.png:

shadows.svg: