sci-biology/bioperl-db: Restrict tests re bug #421701

sci-biology/bioperl-db: Restrict tests re bug #421701

I've tried an excessive amount to get tests working here. But they
still need a lot of love. The work I've done so far only gets
a mysql test instance up, ( and then, only tested with mariadb )

Somebody needs to work out what's missing to provision the databases
that the tests use.

Somebody needs to add support for initializing the other kinds of
database.

Any help here encouraged, but disabling non-functioning tests
is the best we can do for now.

Package-Manager: Portage-2.3.6, Repoman-2.3.2