CMakePresets.json: Fix error message for unsupported package presets

Source/cmCMakePresetsGraph.cxx

@@ -1115,7 +1115,7 @@ const char* cmCMakePresetsGraph::ResultToString(ReadFileResult result)
       return "File version must be 2 or higher for build and test preset "
              "support.";
     case ReadFileResult::PACKAGE_PRESETS_UNSUPPORTED:
-      return "File version must be 5 or higher for package preset support";
+      return "File version must be 6 or higher for package preset support";
     case ReadFileResult::INCLUDE_UNSUPPORTED:
       return "File version must be 4 or higher for include support";
     case ReadFileResult::INVALID_INCLUDE:

Tests/RunCMake/CMakePresetsPackage/UnsupportedVersion-configure-x-stderr.txt

@@ -1,2 +1,2 @@
 ^CMake Error: Could not read presets from [^
-]*/Tests/RunCMake/CMakePresetsPackage/UnsupportedVersion: File version must be 5 or higher for package preset support$
+]*/Tests/RunCMake/CMakePresetsPackage/UnsupportedVersion: File version must be 6 or higher for package preset support$