m/pkg/combinectx: reformat

Seems like this slipped past the cracks on original review - we should
add CI for this.

Change-Id: I35cc1d14710109d4d2d0a60b573400b65cb7d350
Reviewed-on: https://review.monogon.dev/c/monogon/+/212
Reviewed-by: Mateusz Zalega <mateusz@monogon.tech>
diff --git a/metropolis/pkg/combinectx/combinectx.go b/metropolis/pkg/combinectx/combinectx.go
index 5df4ff0..3ff1d72 100644
--- a/metropolis/pkg/combinectx/combinectx.go
+++ b/metropolis/pkg/combinectx/combinectx.go
@@ -18,8 +18,8 @@
 // parent contexts is Done().
 func Combine(a, b context.Context) context.Context {
 	c := &Combined{
-		a: a,
-		b: b,
+		a:     a,
+		b:     b,
 		doneC: make(chan struct{}),
 	}
 	go c.run()
@@ -180,5 +180,3 @@
 	}
 	return nil
 }
-
-