ENSCORESW-1535: allow same GO with different linkage
ENSCORESW-1535: allow same GO with different linkage

muffato/ensembl,Ensembl/ensembl,Ensembl/ensembl,james-monkeyshines/ensembl,muffato/ensembl,james-monkeyshines/ensembl,muffato/ensembl,mjg17/ensembl,danstaines/ensembl,mjg17/ensembl,muffato/ensembl,mjg17/ensembl,danstaines/ensembl,mjg17/ensembl,Ensembl/ensembl,james-monkeyshines/ensembl,danstaines/ensembl,Ensembl/ensembl,james-monkeyshines/ensembl