test: increase coverage internal readline

PR-URL: #24150 Reviewed-By: Ruben Bridgewater <[email protected]> Reviewed-By: James M Snell <[email protected]>

Author: cyanic-webdesign

test/parallel/test-readline-keys.js

@@ -99,11 +99,12 @@ addTest('\n\r\t', [
 ]);
 
 // space and backspace
-addTest('\b\x7f\x1b\b\x1b\x7f \x1b ',[
+addTest('\b\x7f\x1b\b\x1b\x7f\x1b\x1b  \x1b ',[
 {name: 'backspace',sequence: '\b'},
 {name: 'backspace',sequence: '\x7f'},
 {name: 'backspace',sequence: '\x1b\b',meta: true},
 {name: 'backspace',sequence: '\x1b\x7f',meta: true},
+{name: 'space',sequence: '\x1b\x1b ',meta: true},
 {name: 'space',sequence: ' '},
 {name: 'space',sequence: '\x1b ',meta: true},
 ]);