Enable timestamp tooltip on tag

- add tooltip
- add test to check for presence

app/assets/javascripts/registry/explorer/pages/details.vue

@@ -356,7 +356,7 @@ export default {
         </span>
       </template>
       <template #cell(created_at)="{value}">
-        <span ref="rowTime">
+        <span ref="rowTime" v-gl-tooltip :title="tooltipTitle(value)">
           {{ timeFormatted(value) }}
         </span>
       </template>

changelogs/unreleased/216920-bug-restore-exact-time-tooltip-on-last-updated-tag-column.yml

+---
+title: Add tooltip to container registry tags last update column
+merge_request: 31317
+author:
+type: fixed

spec/frontend/registry/explorer/pages/details_spec.js

@@ -142,10 +142,6 @@ describe('Details Page', () => {
     });
 
     describe('row checkbox', () => {
-      beforeEach(() => {
-        mountComponent();
-      });
-
       it('if selected adds item to selectedItems', () => {
         findFirstRowItem('rowCheckbox').vm.$emit('change');
         return wrapper.vm.$nextTick().then(() => {
@@ -277,6 +273,21 @@ describe('Details Page', () => {
         });
       });
     });
+
+    describe('last updated cell', () => {
+      let timeCell;
+
+      beforeEach(() => {
+        timeCell = findFirstRowItem('rowTime');
+      });
+
+      it('displays the time in string format', () => {
+        expect(timeCell.text()).toBe('2 years ago');
+      });
+      it('has a tooltip timestamp', () => {
+        expect(timeCell.attributes('title')).toBe('Sep 19, 2017 1:45pm GMT+0000');
+      });
+    });
   });
 
   describe('pagination', () => {