IWYU: Update for Debian 12 CI job

`include-what-you-use` diagnostics, in practice, are specific to
the environment's compiler and standard library.  Update includes
to satisfy IWYU for our CI job under Debian 12.

Source/cmDebuggerAdapter.h

@@ -16,7 +16,7 @@
 
 #include <cm3p/cppdap/io.h> // IWYU pragma: keep
 
-#include "cmMessageType.h"
+#include "cmMessageType.h" // IWYU pragma: keep
 
 class cmListFileFunction;
 class cmMakefile;