docs: Add 0.3.1 docs (#2939)

Signed-off-by: oliver könig <okoenig@nvidia.com>

Author: ko3n1g

docs/versions1.json

@@ -4,10 +4,16 @@
     "url": "https://docs.nvidia.com/nemo/megatron-bridge/nightly/"
   },
   {
-      "name": "0.3.0 (latest)",
-      "version": "0.3.0",
-      "url": "https://docs.nvidia.com/nemo/megatron-bridge/latest/",
-      "preferred": true
+    "name": "0.3.1 (latest)",
+    "version": "0.3.1",
+    "url": "https://docs.nvidia.com/nemo/megatron-bridge/latest/",
+    "preferred": true
+  },
+  {
+    "name": "0.3.0",
+    "version": "0.3.0",
+    "url": "https://docs.nvidia.com/nemo/megatron-bridge/0.3.0/",
+    "preferred": true
   },
   {
     "version": "0.2.0",
@@ -17,4 +23,4 @@
     "version": "0.1.0",
     "url": "https://docs.nvidia.com/nemo/megatron-bridge/0.1.0/"
   }
-]
+]