Fix memory leaks & data races in tests (#4772)

* Add a few pre-made sanitizer suppressions

* Test Sanitization: Fix threading issues

* Test Sanitization: Allow deletion of PubSub

We still don't delete it in main code, but this allows us to try
deleting it in tests.

* Test Sanitization: Fix some memory leaks

* fix gtest clang-tidy warning

* const emojis test :-)

tests/src/TestHelpers.hpp

@@ -0,0 +1,44 @@
+#pragma once
+
+#include <mutex>
+
+template <typename T>
+class ReceivedMessage
+{
+    mutable std::mutex mutex;
+
+    bool isSet{false};
+    T t;
+
+public:
+    ReceivedMessage() = default;
+
+    explicit operator bool() const
+    {
+        std::unique_lock lock(this->mutex);
+
+        return this->isSet;
+    }
+
+    ReceivedMessage &operator=(const T &newT)
+    {
+        std::unique_lock lock(this->mutex);
+
+        this->isSet = true;
+        this->t = newT;
+
+        return *this;
+    }
+
+    bool operator==(const T &otherT) const
+    {
+        std::unique_lock lock(this->mutex);
+
+        return this->t == otherT;
+    }
+
+    const T *operator->() const
+    {
+        return &this->t;
+    }
+};