Simplify CSS for Merge Requests (list)

by removing rules introduced in the following commits/MRs:

- https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/9020
- https://gitlab.com/gitlab-org/gitlab-foss/-/commit/37eeeb9fca90aa34c502181b9967fb62f9f87752Signed-off-by: Takuya Noguchi <takninnovationresearch@gmail.com>

app/assets/stylesheets/pages/merge_requests.scss

@@ -463,8 +463,7 @@ $mr-widget-min-height: 69px;
 
 .mr-list {
   .merge-request {
-    padding: 10px 0 10px 15px;
-    position: relative;
+    padding: 10px $gl-padding;
     display: flex;
 
     .issuable-info-container {

changelogs/unreleased/restore-spacing-mr-list-for-mobile.yml

+---
+title: Simplify CSS for Merge Requests (list)
+merge_request: 45785
+author: Takuya Noguchi
+type: other