Add optional exit code to list import errors

[drapail]

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Added a flag to list-import-errors command that returns exit code '1' if there are import errors. Will be useful when used in CI pipelines.

[boring-cyborg]

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[potiuk]

I suggest to return it always and remove the flag. There is no particular agreement about the exit codes of CLI commands, and I think it's fair to assume that exit code should be non-zero when there are erros by default.

[potiuk]

(especially that it fails the tests)

[drapail]

I suggest to return it always and remove the flag. There is no particular agreement about the exit codes of CLI commands, and I think it's fair to assume that exit code should be non-zero when there are erros by default.

Agree, fixed it

[boring-cyborg]

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