Misleading output of "No issues found!" when a model is skipped

[peng-hui]

Describe the bug
Modelscan skips a model if it identifies invalid magic number (header) of the model. However, it would still print out

 --- Summary ---

 No issues found! 🎉

--- Skipped ---

Total skipped: 1 - run with --show-skipped to see the full list.

This is kind of misleading because incautious users might ignore the line about the skipped model.

I understand the modelscan produces a different non-zero exit code but I suppose people might not check the exit code.

To Reproduce
Steps to reproduce the behavior:

1. run on a model with an invalid magic number, for example: https://huggingface.co/sentence-transformers/paraphrase-MiniLM-L6-v2/blob/main/openvino/openvino_model.bin
2. modelscan -p openvino_model.bin

Expected behavior
I would expect modelscan to show: modelscan does not know if there is an issue because the model is skipped.

Screenshots
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Environment (please complete the following information):

• OS
  macOS 14.4 (ARM)

• Modelscan Version
  v0.8.1

• Describe the model serialization format that triggered this error (if applicable)
  https://huggingface.co/sentence-transformers/paraphrase-MiniLM-L6-v2/blob/main/openvino/openvino_model.bin

Additional context
Add any other context about the problem here.