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/cmExportTryCompileFileGenerator.cxx

@@ -2,7 +2,6 @@
    file Copyright.txt or https://cmake.org/licensing for details.  */
 #include "cmExportTryCompileFileGenerator.h"
 
-#include <map>
 #include <utility>
 
 #include <cm/memory>
@@ -13,7 +12,6 @@
 #include "cmGeneratorTarget.h"
 #include "cmGlobalGenerator.h"
 #include "cmList.h"
-#include "cmListFileCache.h"
 #include "cmLocalGenerator.h"
 #include "cmMakefile.h"
 #include "cmOutputConverter.h"