Add padding in Merge request analytics table

What does this MR do and why?

On the Merge request analytics page, this MR add padding between the 2 lines of text in the first table cell. This change aligns with the spacing guidelines in Pajamas.

Related KR: https://gitlab.com/gitlab-com/gitlab-OKRs/-/work_items/4493+

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ee/app/assets/javascripts/analytics/merge_request_analytics/components/throughput_table.vue

@@ -288,7 +288,7 @@ export default {
               class="gl-font-weight-bold gl-text-gray-900"
               >{{ item.title }}</gl-link
             >
-            <ul class="horizontal-list gl-mt-2">
+            <ul class="horizontal-list gl-mt-2 gl-mb-0">
               <li class="gl-mr-3">{{ formatMergeRequestId(item.iid) }}</li>
               <li v-if="hasPipelineNodes(item) && item.pipelines.nodes.length" class="gl-mr-3">
                 <gl-icon