Europeana shapes: replace use of SHACL-AF feature with SHACL core functionality

[SvenLieber]

There are currently two Europeana Data Model (EDM) SHACL shapes which use the sh:filterShape feature of SHACL-AF hugomanguinhas/europeana_shapes#1.
These shapes relate to the following EDM constraints

• R-44-PATTERN-MATCHING-ON-RDF-LITERALS
• R-171-VALIDATION-OF-URIS-BY-DEREFERENCING

The reusability of the shapes would be increased if the same constraints would be expressed using SHACL core.
Probably we can use sh:or to achieve the same.