stream_settings: Ignore hover on actions column in tables.

In the dark theme, disable the hover behavior to display sorting options
for actions column in tables (Which doesn't support this).

Matches existing behavior in light theme.

Fixes: #21137

static/styles/dark_theme.css

@@ -83,7 +83,7 @@ body.dark-theme {
     table.table-striped thead.table-sticky-headers th {
         background-color: hsl(0, 0%, 0%);
 
-        &:hover {
+        &:hover:not(.actions) {
             background-color: hsl(211, 29%, 14%);
         }
     }