WebSearch: summarizer unit test update
- Removes self-cite unit tests from summarizer tests since the self-cite functionality have been moved to BibRank as part of commit 1fcbed0ec34a9c31f8a727e21890c529d8222256.
- Adds simple summarizer regression tests.
Co-authored-by: Tibor Simko <tibor.simko@cern.ch>