inconsistent use of "license_expression_spdx"

[armijnhemel]

Description

There is an inconsistency with regards to license_expression_spdx. The following example shows it:

      "license_detections": [
        {
          "license_expression": "gpl-2.0",
          "license_expression_spdx": "GPL-2.0-only",
          "matches": [
            {
              "license_expression": "gpl-2.0-plus",
              "spdx_license_expression": "GPL-2.0-or-later",

As can be seen in matches something else is used, namely spdx_license_expression.