Fixed semantic error with regards to the used flags and binray name in firmware function

src/main.rs

@@ -191,7 +191,7 @@ fn update_firmware() {
         cprintln!("<bold><rev>osupdater: Updating firmware</rev></bold>");
         let mut cmd =
             Command::new(&sudo_bin)
-            .arg(&fwupdmgr_bin).arg("get-updates").arg("-y")
+            .arg(&fwupdmgr_bin).arg("update").arg("-y")
             .stdout(Stdio::inherit()).stderr(Stdio::inherit())
             .spawn().unwrap();
         let _output = cmd.wait();