refactor: Sort includes of touched source files

src/util/feefrac.h

@@ -5,12 +5,13 @@
 #ifndef BITCOIN_UTIL_FEEFRAC_H
 #define BITCOIN_UTIL_FEEFRAC_H
 
-#include <cstdint>
-#include <compare>
-#include <vector>
 #include <span.h>
 #include <util/check.h>
 
+#include <compare>
+#include <cstdint>
+#include <vector>
+
 /** Data structure storing a fee and size, ordered by increasing fee/size.
  *
  * The size of a FeeFrac cannot be zero unless the fee is also zero.