Add define guards around ring buffer

main/include/util/ring_buffer.h

@@ -2,6 +2,9 @@
 #include <mutex>
 #include <optional>
 
+#ifndef RINGBUFFER_H
+#define RINGBUFFER_H
+
 template <typename T>
 class RingBuffer {
 public:
@@ -147,3 +150,5 @@ private:
     // mutable allows const functions to modify/lock the mutex
     mutable std::mutex m_mutex;
 };
+
+#endif //RINGBUFFER_H