fix: removed ref to schema that does not exist (#4760)

data/portal/Dataset mappings.csv

@@ -4,8 +4,6 @@ Dataset mappings,,source,ref,1,TRUE,,Resources,,,,,Id of the resource being mapp
 Dataset mappings,,source dataset,ref,1,TRUE,,Datasets,source,,,,Name of the dataset being mapped from,"DataCatalogueFlat,CohortsStaging,RWEStaging,StudiesStaging",
 Dataset mappings,,target,ref,1,TRUE,,Resources,,,,,Network being mapped to,"DataCatalogueFlat,RWEStaging,StudiesStaging",
 Dataset mappings,,target dataset,ref,1,TRUE,,Datasets,target,,,,"Name of the dataset being mapped to, or harmonised with","DataCatalogueFlat,RWEStaging,StudiesStaging",
-Dataset mappings,,target,ref,1,TRUE,catalogue,Resources,,,,,"Name of the variable being mapped to, or harmonised with",CohortsStaging,
-Dataset mappings,,target dataset,ref,1,TRUE,catalogue,Datasets,target,,,,"Name of the dataset being mapped to, or harmonised with",CohortsStaging,
 Dataset mappings,,order,int,,,,,,,,,Order in which table ETLs should be executed for this source-target combination,"DataCatalogueFlat,CohortsStaging,RWEStaging,StudiesStaging",
 Dataset mappings,,description,text,,,,,,,,,Human readible description of the mapping,"DataCatalogueFlat,CohortsStaging,RWEStaging,StudiesStaging",
 Dataset mappings,,syntax,text,,,,,,,,,"Formal definition of the mapping, ideally in executable code","DataCatalogueFlat,CohortsStaging,RWEStaging,StudiesStaging",