Add exclude option for favicon.ico in template

Author: Madoshakalaka

cargo-generate.toml

@@ -1,5 +1,6 @@
 [template]
 cargo_generate_version = ">=0.9.0"
+exclude = ["favicon.ico"]
 
 [placeholders]
 yew_version = { prompt = "Yew version", choices = ["stable", "next"], default = "stable", type = "string" }