In commit a205ab3ebe a new model
spares_pool has been introduced but the definition introduced by
0b468090e6 was missing the primary key.
In this commit we fixed the definition and add an update script for
already deployed env.
Note: without the PK this creates an error when Running Percona with
pxc_strict_mode == ENFORCING
Story: 2005531
Task: 30658
Change-Id: If70e5df5aea008e8998eaad912ba85dfb6bda77a
Signed-off-by: Sahid Orentino Ferdjaoui <sahid.ferdjaoui@canonical.com>
7971b8ab60