Change label link for Jira issues

Use `label[]=` as param instead of `label_name[]=`. This
is to align with how the backend is handling these labels.

app/assets/javascripts/issuables_list/components/issuable.vue

@@ -187,6 +187,10 @@ export default {
       return isScopedLabel({ title: name }) && this.scopedLabelsAvailable;
     },
     labelHref({ name }) {
+      if (this.isJiraIssue) {
+        return this.issuableLink({ 'labels[]': name });
+      }
+
       return this.issuableLink({ 'label_name[]': name });
     },
     onSelect(ev) {

spec/frontend/issuables_list/components/issuable_spec.js

@@ -333,6 +333,33 @@ describe('Issuable component', () => {
     });
   });
 
+  describe('with labels for Jira issuable', () => {
+    beforeEach(() => {
+      issuable.labels = [...testLabels];
+      issuable.external_tracker = 'jira';
+
+      factory({ issuable });
+    });
+
+    it('renders labels', () => {
+      factory({ issuable });
+
+      const labels = findLabels().wrappers.map(label => ({
+        href: label.props('target'),
+        text: label.text(),
+        tooltip: label.attributes('description'),
+      }));
+
+      const expected = testLabels.map(label => ({
+        href: mergeUrlParams({ 'labels[]': label.name }, TEST_BASE_URL),
+        text: label.name,
+        tooltip: label.description,
+      }));
+
+      expect(labels).toEqual(expected);
+    });
+  });
+
   describe.each`
     weight
     ${0}