*: 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/pkg/logtree/logtree.go b/metropolis/pkg/logtree/logtree.go
index 8523569..a21545f 100644
--- a/metropolis/pkg/logtree/logtree.go
+++ b/metropolis/pkg/logtree/logtree.go
@@ -21,7 +21,7 @@
 	"strings"
 	"sync"
 
-	"git.monogon.dev/source/nexantic.git/metropolis/pkg/logbuffer"
+	"source.monogon.dev/metropolis/pkg/logbuffer"
 )
 
 // LogTree is a tree-shaped logging system. For more information, see the package-level documentation.