Raise group_concat_max_len in MLSS adaptor test
Raise group_concat_max_len in MLSS adaptor test

This will avoid spurious test failures caused by
truncation of the species_set GROUP_CONCAT value.

Ensembl/ensembl-compara,Ensembl/ensembl-compara,Ensembl/ensembl-compara,Ensembl/ensembl-compara,Ensembl/ensembl-compara,Ensembl/ensembl-compara,Ensembl/ensembl-compara,Ensembl/ensembl-compara