fix: Systems can be added twice because of missing check by type

[Dan-Crane]

Description

Added a check when adding a system that is already in _systemsByType

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Related Issues

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[wolfenrain]

@Dan-Crane are you able to follow-up on this to get the workflows unblocked?

[Dan-Crane]

@wolfenrain hi!) Do i understand correctly, i need to correct what CICD is swearing at?