Fix: remove sortBy prop default value

[Clebal]

Using [] as default sortBy value makes the execution to break due to it's an invalid sortBy value.

[coveralls]

Pull Request Test Coverage Report for Build 1628021541

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 68.913%

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Totals
Change from base Build 1626881185:	0.0%
Covered Lines:	1044
Relevant Lines:	1424

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💛 - Coveralls

[alasarr]

Can you provide an example of the failure?

[Clebal]

@alasarr

If you want to get the features of certain source with certain filters, but you don't want to sort the features:

executeTask(sourceId, Methods.FEATURES_RAW, { filters: sourceFilters })

It makes the code break, because in sorting.js we have a validation of sortBy prop which cannot be an empty array. If you don't want to sort by anything, then sortBy should be undefined.