fix build

Cargo.toml

@@ -10,7 +10,7 @@ author = "https://djkato.net"
 discord-rich-presence = "0.2.2"
 regex = "1.6.0"
 tray-item = "0.7.0"
-windres = "*"
+
 [dependencies.windows]
 version = "0.39.0"
 features = [
@@ -20,3 +20,5 @@ features = [
     "Win32_System_Threading",
     "Win32_UI_WindowsAndMessaging",
 ]
+[target.'cfg(windows)'.build-dependencies]
+windres = "0.2.2"

build.rs

@@ -1,5 +1,10 @@
+#[cfg(windows)]
+extern crate windres;
+
+#[cfg(windows)]
 use windres::Build;
 
+#[cfg(windows)]
 fn main() {
     Build::new().compile("./icon/tray-icon.rc").unwrap();
 }