Dropdown - Allow to disable Popper.js style (#24092)

* Dropdown - Allow to disable Popper.js style

* Update dropdown.js

* Update dropdown.html

* copy changes

js/tests/unit/dropdown.js

@@ -908,4 +908,34 @@ $(function () {
       })
     $textarea.trigger('click')
   })
+
+  QUnit.test('should not use Popper.js if display set to static', function (assert) {
+    assert.expect(1)
+    var dropdownHTML =
+        '<div class="dropdown">' +
+        '<a href="#" class="dropdown-toggle" data-toggle="dropdown" data-display="static">Dropdown</a>' +
+        '<div class="dropdown-menu">' +
+        '<a class="dropdown-item" href="#">Secondary link</a>' +
+        '<a class="dropdown-item" href="#">Something else here</a>' +
+        '<div class="divider"/>' +
+        '<a class="dropdown-item" href="#">Another link</a>' +
+        '</div>' +
+        '</div>'
+
+    var $dropdown = $(dropdownHTML)
+      .appendTo('#qunit-fixture')
+      .find('[data-toggle="dropdown"]')
+      .bootstrapDropdown()
+    var done = assert.async()
+    var dropdownMenu = $dropdown.next()[0]
+
+    $dropdown.parent('.dropdown')
+      .on('shown.bs.dropdown', function () {
+        // Popper.js add this attribute when we use it
+        assert.strictEqual(dropdownMenu.getAttribute('x-placement'), null)
+        done()
+      })
+
+    $dropdown.trigger('click')
+  })
 })