fix: Long delay in listDisplays() xrandr call #302 (#303)

Call xrandr with the `--current` switch, which skips hardware polling and uses the current screen configuration directly.  This eliminates a long (~1.6 second) delay that locks up the system.

Co-authored by: Elliott Partridge <[email protected]>

lib/linux/index.js

@@ -115,7 +115,7 @@ function parseDisplaysOutput (out) {
 
 function listDisplays () {
   return new Promise((resolve, reject) => {
-    exec('xrandr', (err, stdout) => {
+    exec('xrandr --current', (err, stdout) => {
       if (err) {
         return reject(err)
       }