Make ScienceDirect a SearchBasedFetcher to be able to use an API key in the UI

[Siedlerchr]

Is your suggestion for improvement related to a problem? Please describe.
ScienceDirect is missing here in the UI because it's not a SearchbasedFetcher.

Describe the solution you'd like
Implement the search based fetcher interface

Additional context

[omkarrr2533]

/assign-me

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