p2p topology file for cardano mainnet

TODO: do we want to commit it or keep it in a branch?

Co-authored-by: Armando Santos <bolt12@users.noreply.github.com>
Co-authored-by: Karl Knutsson <karknu@users.noreply.github.com>
Co-authored-by: Marcin Szamotulski <coot@users.noreply.github.com>

configuration/cardano/mainnet-p2p-toplogy.json

@@ -0,0 +1,18 @@
+{
+  "LocalRoots": {
+    "groups": []
+  },
+  "PublicRoots": [
+    {
+      "publicRoots": {
+        "accessPoints": [
+          {
+            "address": "relays-new.cardano-mainnet.iohk.io",
+            "port": 3001
+          }
+        ],
+        "advertise": false
+      }
+    }
+  ]
+}