Bump the nuget-dependencies group with 1 update (#44)

Bumps demaconsulting.spdxtool from 2.8.0 to 2.9.0

---
updated-dependencies:
- dependency-name: demaconsulting.spdxtool
  dependency-version: 2.9.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: nuget-dependencies
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.config/dotnet-tools.json

@@ -9,7 +9,7 @@
       ]
     },
     "demaconsulting.spdxtool": {
-      "version": "2.8.0",
+      "version": "2.9.0",
       "commands": [
         "spdx-tool"
       ]