misc: Further improve imports styling

By introducing `imports_granularity="Module"` format strategy,
effectively groups imports from the same module into one line or block,
improving maintainability and readability.

Signed-off-by: Ruoqing He <heruoqing@iscas.ac.cn>

vmm/src/api/dbus/mod.rs

@@ -26,8 +26,7 @@ use crate::api::{
     VmSendMigration, VmShutdown, VmSnapshot, VmmPing, VmmShutdown,
 };
 use crate::seccomp_filters::{get_seccomp_filter, Thread};
-use crate::{Error as VmmError, Result as VmmResult};
-use crate::{NetConfig, VmConfig};
+use crate::{Error as VmmError, NetConfig, Result as VmmResult, VmConfig};
 
 pub type DBusApiShutdownChannels = (oneshot::Sender<()>, oneshot::Receiver<()>);