18: Added SPDX header in IconHelper file

[Ayko1595]

Pull Request Template

Description

Please include a summary of the change and which issue is fixed or added. Please also include relevant motivation and context. List any dependencies that are required for this change.

Fixes #18

Checklist

• [x] My contributions and commit messages follows the style guidelines of this project
• [x] I have made corresponding changes to the documentation
• [x] New and existing unit tests pass locally with my changes
• [x] The Pull Request has an informative and human-readable title
• [x] Changes are limited to a single goal (avoid scope creep)
• [x] Code can be automatically merged (no conflicts)
• [x] I confirm that I have read any Contribution guidelines (CONTRIBUTING)
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[Ayko1595]

Missade dessvärre att köra en sign-off på commit:en