Fix PCI devices DB API tests

Stub values of PCI device addresses, which are used in
DB API tests of PCI devices code, do not fit into 'address'
column of 'pci_devices' table (that is of type VARCHAR(12)),
because they actually have length of 13 characters.

The tests succeed with SQLite, but fail with both PostgreSQL
and MySQL.

Blueprint: db-api-tests-on-all-backends

Change-Id: I5757fa07618d9a0e944704c8fbff3c6bcb15d37d
Merge "Fix PCI devices DB API tests"