Update system-mysql internal DB from MySQL 5.7 to 8.0

[miguelsorianod]

The change of image also implies an automated upgrade from
MySQL 5.7 to 8.0 when coming from an older 3scale installation
where 5.7 is used. There is no need for a custom upgrade procedure.

The data migration is performed automatically when changing the image.

On the product side, the image to be set will be:
registry.redhat.io/rhscl/mysql-80-rhel7:8.0

JIRA: https://issues.redhat.com/browse/THREESCALE-7786
which depends on https://issues.redhat.com/browse/THREESCALE-6825

Verification steps

Deploy 3scale with the APIManager

k apply -f - <<EOF
apiVersion: apps.3scale.net/v1alpha1
kind: APIManager
metadata:
  name: apimanager
spec:
  wildcardDomain: ns.apps.example.com

Wait for the deployment to be ready

oc wait --for=condition=available apimanager/apimanager --timeout=-1s

Check mysql 8 is running

oc exec -t dc/system-mysql -- /opt/rh/rh-mysql80/root/usr/libexec/mysqld --version
/opt/rh/rh-mysql80/root/usr/libexec/mysqld  Ver 8.0.21 for Linux on x86_64 (Source distribution)

[miguelsorianod]

At the moment this cannot be merged due to system's pre-hook pod is failing to start after this changes.
This issue has been identified in https://issues.redhat.com/browse/THREESCALE-6825 and this issue cannot be merged until that issue is resolved and this PR is tested again after those changes to verify that all works. The PR will need to be tested with both the upstream and product image, including the upgrade between mysql 5.7 and 8

[eguzki]

this was a very easy one :)

[eguzki]

starting command line or env vars... all remain the same from 5.7 to 8? Seems like 5.8 more than 8.0 :)

[miguelsorianod]

starting command line or env vars... all remain the same from 5.7 to 8? Seems like 5.8 more than 8.0 :)

It should remain the same. It's 8.0. MySQL 5.8 does not exist.

I take the ownership of the PR

[codeclimate]

An error occurred when fetching issues.

View more on Code Climate.

[eguzki]

@MStokluska added verification steps

[MStokluska]

Reviewed code and tested in an upgrade scenario on my cluster. Looks good to me.
/lgtm

[MStokluska]

/approve

[MStokluska]

Looks good to me, verified changes on cluster and code looks good as well