ci: Enable IWYU in src/kernel directory

Suggested https://github.com/bitcoin/bitcoin/pull/25308#discussion_r892505713

src/kernel/coinstats.cpp

@@ -4,16 +4,32 @@
 
 #include <kernel/coinstats.h>
 
+#include <chain.h>
 #include <coins.h>
 #include <crypto/muhash.h>
 #include <hash.h>
+#include <node/blockstorage.h>
+#include <primitives/transaction.h>
+#include <script/script.h>
 #include <serialize.h>
+#include <span.h>
+#include <streams.h>
+#include <sync.h>
+#include <tinyformat.h>
 #include <uint256.h>
+#include <util/check.h>
 #include <util/overflow.h>
 #include <util/system.h>
 #include <validation.h>
+#include <version.h>
 
+#include <cassert>
+#include <iosfwd>
+#include <iterator>
 #include <map>
+#include <memory>
+#include <string>
+#include <utility>
 
 namespace kernel {