harvester validator doesn't enforce file size for fetch via url #6081

validator accepts fetching a dcatus document via url but should raise an exception when the file size of document exceeds 10mb. this source which is ~20mb can be fetched no problem. that's not the intended behavior.

How to reproduce

use the source above in the validator and fetch it via url

Expected behavior

error to be displayed on the page indicating the file is too big

Actual behavior

file is fetched and processed normally

Sketch

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