pub glib-build-tools behind gtk feature flag

Cargo.toml

@@ -62,7 +62,7 @@ windows = {  version = "0.54.0", features = [
 ] }
 
 [build-dependencies]
-glib-build-tools = "0.19.0"
+glib-build-tools = { version = "0.19.0", optional = true }
 
 [features]
 default = ["wayland", "x11", "xdg_desktop_portal", "libei", "gtk"]
@@ -70,4 +70,4 @@ wayland = ["dep:wayland-client", "dep:wayland-protocols", "dep:wayland-protocols
 x11 = ["dep:x11"]
 xdg_desktop_portal = ["dep:ashpd"]
 libei = ["dep:reis", "dep:ashpd"]
-gtk = ["dep:gtk", "dep:adw", "dep:async-channel"]
+gtk = ["dep:gtk", "dep:adw", "dep:async-channel", "dep:glib-build-tools"]

build.rs

@@ -1,5 +1,6 @@
 fn main() {
     // composite_templates
+    #[cfg(feature = "gtk")]
     glib_build_tools::compile_resources(
         &["resources"],
         "resources/resources.gresource.xml",