License headers: add SPDX header

Also include "addons_core" in license check.

scripts/addons_core/bl_pkg/example_extension/__init__.py

@@ -1,3 +1,5 @@
+# SPDX-FileCopyrightText: 2024 Blender Foundation
+#
 # SPDX-License-Identifier: GPL-2.0-or-later
 
 def register():

scripts/addons_core/bl_pkg/extensions_map_from_legacy_addons.py

@@ -1,3 +1,7 @@
+# SPDX-FileCopyrightText: 2024 Blender Foundation
+#
+# SPDX-License-Identifier: GPL-2.0-or-later
+
 # This is a data file that is evaluated directly (not imported).
 # NOTE: this can be removed once upgrading from 4.1 is no longer relevant.
 {

tools/check_source/check_licenses.py

@@ -540,7 +540,6 @@ def main() -> None:
                 "./lib",
                 # Just data.
                 "./doc/python_api/examples",
-                "./scripts/addons_core",
                 "./scripts/presets",
                 "./scripts/templates_py",