Add healthcheck to all stores

honeypot/ssh/store/memory.go

@@ -142,6 +142,10 @@ func (ms *MemoryStore) Query(query AttemptQuery) ([]models.LoginAttempt, error)
 	return results, nil
 }
 
+func (s *MemoryStore) IsHealthy() bool {
+	return true
+}
+
 func toResults(m map[string]int) []StatsResult {
 	var results []StatsResult