add metadata for cube filename

meta_info/nomad_meta_info/fhi_aims.nomadmetainfo.json

@@ -1600,5 +1600,14 @@
         "x_fhi_aims_section_vdW_TS"
       ],
       "units": "J"
+    }, {
+      "description": "filename of cube file",
+      "dtypeStr": "C",
+      "name": "x_fhi_aims_cube_filename",
+      "repeats": true,
+      "shape": [],
+      "superNames": [
+        "section_single_configuration_calculation"
+      ]
     }]
 }