Revert "Allow multiple delegated tooltip selectors on a node"

This reverts commit 1b3237629a.
This reverts PR #14189 because it caused major regressions.

Fixes #15168.

We'll try to revisit #14167's feature request in Bootstrap v4.

[skip validator]

js/tests/unit/tooltip.js

@@ -235,37 +235,6 @@ $(function () {
     equal($('.tooltip').length, 0, 'tooltip was removed from dom')
   })
 
-  test('should show tooltips with different delegate selectors on the same node on click', function () {
-    var tooltipHTML = '<div>'
-        + '<a href="#" class="first" rel="tooltip" title="First delegated tooltip"/>'
-        + '<a href="#" class="second" rel="tooltip" title="Second delegated tooltip"/>'
-        + '</div>'
-
-    var $div = $(tooltipHTML)
-      .append()
-      .appendTo('#qunit-fixture')
-      .bootstrapTooltip({
-        selector: 'a.first[rel="tooltip"]',
-        trigger: 'click'
-      })
-      .bootstrapTooltip({
-        selector: 'a.second[rel="tooltip"]',
-        trigger: 'click'
-      })
-
-    $div.find('a.first').click()
-    ok($('.tooltip').is('.fade.in'), 'first tooltip is faded in')
-
-    $div.find('a.first').click()
-    equal($('.tooltip').length, 0, 'first tooltip was removed from dom')
-
-    $div.find('a.second').click()
-    ok($('.tooltip').is('.fade.in'), 'second tooltip is faded in')
-
-    $div.find('a.second').click()
-    equal($('.tooltip').length, 0, 'second tooltip was removed from dom')
-  })
-
   test('should show tooltip when toggle is called', function () {
     $('<a href="#" rel="tooltip" title="tooltip on toggle"/>')
       .appendTo('#qunit-fixture')