Add inventory-item-not-system-or-validation Constraint

[Gabeblis]

Committer Notes

Purpose

This PR aims to add the inventory-item-not-system-or-validation constraint which ensures that an inventory item MUST NOT reference a "system" component nor a "validation" component.

Changes

Added constraint:

• inventory-item-not-system-or-validation

Added valid/invalid test content:

• ssp-inventory-item-not-system-or-validation-INVALID.xml

Added yaml files for testing:

• Pass/fail yaml tests added for each of the above constraints.

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By submitting a pull request, you are agreeing to provide this contribution under the CC0 1.0 Universal public domain dedication.

[Rene2mt]

Nice work!