tooltip: Improve tooltip placement for search users icon in right sidebar.

Similar to the previous commit, the tooltip was not
completely visible in this case and this bug was
similar to the one corrected in recipient bar icons.

static/js/tippyjs.js

@@ -181,7 +181,7 @@ export function initialize() {
     // ensures that tooltip doesn't hide behind the message
     // box or it is not limited by the parent container.
     delegate("body", {
-        target: [".recipient_bar_icon", ".sidebar-title"],
+        target: [".recipient_bar_icon", ".sidebar-title", "#user_filter_icon"],
         placement: "top",
         appendTo: () => document.body,
     });