fix(cmakev2/project): unset global variables in idf_project_init macro

The idf_project_init macro is evaluated within the global variable
scope, and currently, there are a few variables still set. Let's ensure
all variables are properly unset to avoid polluting the global variable
namespace.

Signed-off-by: Frantisek Hrbata <frantisek.hrbata@espressif.com>

tools/cmakev2/project.cmake

@@ -596,6 +596,7 @@ macro(idf_project_init)
             idf_die("sdkconfig.cmake file not found.")
         endif()
         include("${sdkconfig_cmake}")
+        unset(sdkconfig_cmake)
 
         # Initialize the target architecture based on the configuration
         # Ensure this is done after including the sdkconfig.
@@ -636,6 +637,7 @@ macro(idf_project_init)
                 idf_component_include("${component_name}")
             endforeach()
         endif()
+        unset(include_all_components)
 
         idf_build_set_property(__PROJECT_INITIALIZED YES)
     endif()