lib: converted element to lowercase in tty.js

Converted the first element "Eterm" in TERM_ENVS array to "eterm"

PR-URL: #26121
Fixes: #26077
Reviewed-By: Colin Ihrig <[email protected]>
Reviewed-By: Richard Lau <[email protected]>
Reviewed-By: Anto Aravinth <[email protected]>
Reviewed-By: Weijia Wang <[email protected]>
Reviewed-By: Yuta Hiroto <[email protected]>
Reviewed-By: Luigi Pinca <[email protected]>
Reviewed-By: James M Snell <[email protected]>
Reviewed-By: Сковорода Никита Андреевич <[email protected]>
Reviewed-By: Minwoo Jung <[email protected]>

lib/internal/tty.js

@@ -37,7 +37,7 @@ const COLORS_16m = 24;
 // distribution of this file, with or without modification, are permitted
 // provided the copyright notice and this notice are preserved.
 const TERM_ENVS = [
-  'Eterm',
+  'eterm',
   'cons25',
   'console',
   'cygwin',