twister: unit tests for config_parser.py

[mdubielx]

unit tests for config_parser

[github-actions]

Hello @mdubielx, and thank you very much for your first pull request to the Zephyr project!
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[github-actions]

This pull request has been marked as stale because it has been open (more than) 60 days with no activity. Remove the stale label or add a comment saying that you would like to have the label removed otherwise this pull request will automatically be closed in 14 days. Note, that you can always re-open a closed pull request at any time.

[gbarkadiusz]

Please remove DNM label and add description.

[gbarkadiusz]

Please do not use shortcuts form in titles.

[LukaszMrugala]

A lot of repeated code; parametrise what you can.

[github-actions]

Hi @mdubielx!
Congratulations on getting your very first Zephyr pull request merged 🎉🥳. This is a fantastic achievement, and we're thrilled to have you as part of our community!

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Thank you for your valuable input, and we look forward to seeing more of your contributions in the future! 🪁