fixup! rustdoc: make the resize handle easier to find

Author: notriddle

tests/rustdoc-gui/sidebar-resize.goml

@@ -12,10 +12,10 @@ set-local-storage: {"rustdoc-hide-sidebar": "false"}
 
 // Now same thing, but for source code
 go-to: "file://" + |DOC_PATH| + "/src/test_docs/lib.rs.html"
-assert-property: (".sidebar", {"clientWidth": "49"})
+assert-property: (".sidebar", {"clientWidth": "46"})
 drag-and-drop: ((52, 100), (185, 100))
-assert-property: (".sidebar", {"clientWidth": "181"})
+assert-property: (".sidebar", {"clientWidth": "151"})
 drag-and-drop: ((185, 100), (5, 100))
 // instead of hiding the sidebar entirely, this
 // will switch to the toggle mode
-assert-property: (".sidebar", {"clientWidth": "49"})
+assert-property: (".sidebar", {"clientWidth": "46"})