update code comment

Signed-off-by: Shlomi Noach <[email protected]>

go/vt/vttablet/onlineddl/executor.go

@@ -152,7 +152,7 @@ type Executor struct {
 	// A UUID listed in this map stands for a migration that is executing, and that this executor can control.
 	// Migrations found to be running which are not listed in this map will either:
 	// - be adopted by this executor (possible for vreplication migrations), or
-	// - be terminated (example: pt-osc migration gone rogue, process still running even as the migration failed)
+	// - be terminated
 	// The Executor auto-reviews the map and cleans up migrations thought to be running which are not running.
 	ownedRunningMigrations        sync.Map
 	vreplicationLastError         map[string]*vterrors.LastError