docs: simplify repository links

docs.json

@@ -172,11 +172,6 @@
         "label": "项目源码",
         "href": "https://gitea.kenanzhu.com/AutoLibrary/AutoLibrary",
         "icon": "/images/repositories/gitea.svg"
-      },
-      {
-        "label": "手册源码",
-        "href": "https://gitlab.com/KenanZhu/AutoLibraryManuals",
-        "icon": "/images/repositories/gitlab.svg"
       }
     ]
   },
@@ -194,11 +189,7 @@
         "header": "代码仓库",
         "items": [
           {
-            "label": "AutoLibrary（Gitea）",
-            "href": "https://gitea.kenanzhu.com/AutoLibrary/AutoLibrary"
-          },
-          {
-            "label": "用户手册（GitLab）",
+            "label": "用户手册",
             "href": "https://gitlab.com/KenanZhu/AutoLibraryManuals"
           }
         ]