fix wasm

Author: 38

examples/wasm-demo/Cargo.toml

@@ -9,7 +9,7 @@ crate-type=["cdylib"]
 
 [dependencies]
 plotters = {path = "../.."}
-plotters-canvas = "0.1.*"
+plotters-canvas = "^0.3.*"
 wasm-bindgen = "0.2.62"
 wee_alloc = "0.4.5"
 web-sys = { version = "0.3.39", features = ["HtmlCanvasElement"] }