add MaterialCitation to allowed basisOfRecords

[rubenpp7]

Rationale:
https://docs.gbif.org/course-data-use/en/basis-of-record.html

Changes needed in:

EMODnetBiocheck/R/checkdataset.R

Lines 1211 to 1212 in 5729844

	basORec_valid <- c("PreservedSpecimen", "FossilSpecimen", "LivingSpecimen", "HumanObservation",
	"MachineObservation", "MaterialSample", "Occurrence")