Update shiny version missing in #309 (#312)

# Pull Request

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Fixes #311

#### Changes description

- Bumps `shiny` to `v1.11.1` when the change was introduced
- This is optional as it appears to work with previous versions, @vedhav
any specific reason why it wasn't added in the previous PR?
- Fixes behavior back to default (`event` -> `deferred`)
    - with `event` priority the trigger enters an infinite loop

> Provide a new value of {priority: "event"} to always send now, even if
the value hasn't changed.

---------

Signed-off-by: André Veríssimo <[email protected]>
Signed-off-by: Vedha Viyash <[email protected]>
Co-authored-by: Vedha Viyash <[email protected]>

Author: averissimo

DESCRIPTION

@@ -31,7 +31,7 @@ Imports:
     lifecycle (>= 0.2.0),
     methods,
     rtables (>= 0.6.6),
-    shiny (>= 1.6.0),
+    shiny (>= 1.8.1),
     shinyjs (>= 2.1.0),
     shinyWidgets (>= 0.5.1),
     styler (>= 1.2.0)

inst/draggable-buckets/draggable-buckets.js

@@ -90,7 +90,7 @@ $.extend(draggableBuckets, {
   subscribe: function (el, callback) {
     if (this.observers === undefined) this.observers = {};
     this.observers[el] = new MutationObserver(function () {
-      callback({ priority: "event" });
+      callback({ priority: "deferred" });
     });
     this.observers[el].observe(el, {
       subtree: true,