Set text color to --result-text-color

Previously, we set the text color to `--search-text-color`.
That would create contrast issues if search background
color is considerably different from the window color.

Since the background color for the HTML is set to
`--window-color`, and since in the Alfred UI, the
result text is displayed directly on top of it, we
can be sure that `--window-color` and `--result-text-color`
will always provide good contrast. (and if they don't,
then the Alfred theme is as useless as the extra pane).

dict-entry.css

@@ -1,14 +1,14 @@
 :root
 {
     --secondary-label: var(--result-subtext-color, #eee);
-    --text: var(--search-text-color, #eee);
+    --text: var(--result-text-color, #eee);
     --link: var(--result-text-colorSelected, var(--link));
 }
 
 html
 {
     background-color: var(--window-color, #1d1e28);
-    color: var(--search-text-color, #eee);
+    color: var(--result-text-color, #eee);
 }
 
 body