*: git.monogon.dev -> source.monogon.dev

This implements T882, setting our (virtual) GOPATH to source.monogon.dev
for this repository.

Test Plan: Refactor, CI only.

X-Origin-Diff: phab/D686
GitOrigin-RevId: c5e2309089948ffc3a98e68e2e0e1cbb157d3a36
diff --git a/metropolis/node/core/cluster/node.go b/metropolis/node/core/cluster/node.go
index 4240428..92ff072 100644
--- a/metropolis/node/core/cluster/node.go
+++ b/metropolis/node/core/cluster/node.go
@@ -28,8 +28,8 @@
 	"go.etcd.io/etcd/clientv3"
 	"golang.org/x/sys/unix"
 
-	"git.monogon.dev/source/nexantic.git/metropolis/node/core/localstorage"
-	ipb "git.monogon.dev/source/nexantic.git/metropolis/proto/internal"
+	"source.monogon.dev/metropolis/node/core/localstorage"
+	ipb "source.monogon.dev/metropolis/proto/internal"
 )
 
 // Node is a Metropolis cluster member. A node is a virtual or physical machine running Metropolis. This object