js: Convert space after tick in menus to a space character

Older Firefox versions don't support "-moz-appearance: none" on radio
buttons, which seems to mean that the specifies padding for them
doesn't appear.  Using a space character instead works fine, so do that
everywhere.  This seems to move the text slightly closer to the tick on
browsers that do support "appearance: none", but the result is quite
acceptable.

This also makes the focus outline on the ticks slightly less weird.

html/jspage.pl

@@ -215,7 +215,6 @@ EOF
     appearance: none;
     margin: initial;
     font: inherit;
-    padding-right: 0.5em;
 }
 
 #gamemenu .tick::before {