Set IdentityService to start before PersistenceService

[richturner]

[richturner]

This should solve the service startup issues seen on Balena, feel free to give it a try @pankalog

If ok then it can be approved and merged, would suggest removing the keycloak healthcheck PR then also due to reason mentioned there

[richturner]

@pankalog Did you get a chance to try this branch?

[pankalog]

@pankalog Did you get a chance to try this branch?

No unfortunately, I wanted to but it's a quite big change and I'd like to do more extensive testing on the devices. Will try to do it this week!