Remove extra grid cell space from header in autofilter child popup

- we need to also consider `th` tag to make it display none
- it's a empty text span so do not that extra space.
Signed-off-by: Darshan-upadhyay1110 <darshan.upadhyay@collabora.com>
Change-Id: Ib83d42f64a0115fdc4d17a8f7e952419a84cc9d5

browser/css/jsdialogs.css

@@ -1106,6 +1106,8 @@ input[type='number']:hover::-webkit-outer-spin-button {
 }
 
 /* hide radio in filter by color */
+.jsdialog.autofilter #background tr th:nth-of-type(1),
+.jsdialog.autofilter #textcolor tr th:nth-of-type(1),
 .jsdialog.autofilter #background tr td:nth-of-type(1),
 .jsdialog.autofilter #textcolor tr td:nth-of-type(1) {
 	display: none;