alphaplan_fwr: Remove obsolete pkg.py artifact

The pkg.py file is no longer deployed by the build process.

See commit
seco-ne/yocto/layers/meta-seconorth-distro@e79e8579

scripts/generate_alphaplan_fwr_file.py

@@ -194,7 +194,7 @@ def generate_fwr_articles(
 
     else:
         # Same process for a yocto release
-        subarticles = [ApKeys.YOCTO_PKG_PY, ApKeys.YOCTO_FNG_INSTALL, ApKeys.YOCTO_FS]
+        subarticles = [ApKeys.YOCTO_FNG_INSTALL, ApKeys.YOCTO_FS]
         for key in subarticles:
             stueckliste.append(
                 generate_ap_subarticle(