Fix gitea user to allow sending email

In order to send email, the gitea user needs to be in the mail-robot
group.

Fixes: #220

m/owl1/configuration.nix

@@ -20,7 +20,7 @@
       address = "10.0.40.1";
       prefixLength = 24;
     } ];
-    interfaces.ibp5s0.ipv4.addresses = [ {
+    interfaces.ibs785.ipv4.addresses = [ {
       address = "10.0.42.1";
       prefixLength = 24;
     } ];

m/owl2/configuration.nix

@@ -21,7 +21,7 @@
       prefixLength = 24;
     } ];
     # Watch out! The OmniPath device is not in the same place here:
-    interfaces.ibp129s0.ipv4.addresses = [ {
+    interfaces.ibs801.ipv4.addresses = [ {
       address = "10.0.42.2";
       prefixLength = 24;
     } ];