Remove Unnecessary Includes in Headers (#4275)

* refactor: remove unnecessary includes in headers

* fix: formatting

* chore: changelog

* fix: scrollbar

* fix: suggestions and old appbase remains

* fix: suggestion

* fix: missing Qt forward declarations

* fix: another qt include

* fix: includes for precompiled-headers=off

* Add missing `<memory>` includes

* Add missing `#pragma once`

* Fix tests

Co-authored-by: Rasmus Karlsson <rasmus.karlsson@pajlada.com>

src/providers/seventv/eventapi/SeventvEventAPIClient.cpp

@@ -1,5 +1,6 @@
 #include "providers/seventv/eventapi/SeventvEventAPIClient.hpp"
 
+#include "providers/seventv/eventapi/SeventvEventAPISubscription.hpp"
 #include "providers/twitch/PubSubHelpers.hpp"
 
 #include <utility>

src/providers/seventv/eventapi/SeventvEventAPIClient.hpp

@@ -1,6 +1,8 @@
 #pragma once
 
 #include "providers/liveupdates/BasicPubSubClient.hpp"
+// this needs to be included for the specialization
+// of std::hash for SeventvEventAPISubscription
 #include "providers/seventv/eventapi/SeventvEventAPISubscription.hpp"
 
 namespace chatterino {

src/providers/seventv/eventapi/SeventvEventAPIMessage.hpp

@@ -1,6 +1,6 @@
 #pragma once
 
-#include "providers/seventv/SeventvEventAPI.hpp"
+#include "providers/seventv/eventapi/SeventvEventAPISubscription.hpp"
 
 #include <boost/optional.hpp>
 #include <magic_enum.hpp>