Update active branch for the docs website

Author: GromNaN

.doctrine-project.json

@@ -5,17 +5,23 @@
     "slug": "mongodb-odm",
     "docsSlug": "doctrine-mongodb-odm",
     "versions": [
+        {
+            "name": "2.13",
+            "branchName": "2.13.x",
+            "slug": "latest",
+            "upcoming": true
+        },
         {
             "name": "2.12",
             "branchName": "2.12.x",
             "slug": "latest",
-            "upcoming": true
+            "current": true
         },
         {
             "name": "2.11",
             "branchName": "2.11.x",
             "slug": "2.11",
-            "current": true
+            "maintained": false
         },
         {
             "name": "2.10",