Improve arm build

[hors]

• we build 'linux/amd64' by default if DOCKER_DEFAULT_PLATFORM var is not set
• user can build both 'linux/amd64' and 'linux/arm64'. For it user should use DOCKER_DEFAULT_PLATFORM='linux/amd64,linux/arm64' variable
• user also can build only 'linux/arm64' using DOCKER_DEFAULT_PLATFORM var like 'DOCKER_DEFAULT_PLATFORM='linux/arm64'

CHANGE DESCRIPTION

Problem: Short explanation of the problem.

Cause: Short explanation of the root cause of the issue if applicable.

Solution: Short explanation of the solution we are providing with this PR.

CHECKLIST

Jira

• [ ] Is the Jira ticket created and referenced properly?
• [ ] Does the Jira ticket have the proper statuses for documentation (Needs Doc) and QA (Needs QA)?
• [ ] Does the Jira ticket link to the proper milestone (Fix Version field)?

Tests

• [ ] Is an E2E test/test case added for the new feature/change?
• [ ] Are unit tests added where appropriate?
• [ ] Are OpenShift compare files changed for E2E tests (compare/*-oc.yml)?

Config/Logging/Testability

• [ ] Are all needed new/changed options added to default YAML files?
• [ ] Did we add proper logging messages for operator actions?
• [ ] Did we ensure compatibility with the previous version or cluster upgrade process?
• [ ] Does the change support oldest and newest supported PXC version?
• [ ] Does the change support oldest and newest supported Kubernetes version?

[JNKPercona]

Test name	Status
affinity-8-0	passed
auto-tuning-8-0	passed
cross-site-8-0	passed
demand-backup-cloud-8-0	passed
demand-backup-encrypted-with-tls-8-0	passed
demand-backup-8-0	passed
haproxy-5-7	passed
haproxy-8-0	passed
init-deploy-5-7	passed
init-deploy-8-0	passed
limits-8-0	passed
monitoring-2-0-8-0	failure
one-pod-5-7	passed
one-pod-8-0	passed
pitr-8-0	passed
pitr-gap-errors-8-0	passed
proxy-protocol-8-0	passed
proxysql-sidecar-res-limits-8-0	passed
pvc-resize-5-7	passed
pvc-resize-8-0	passed
recreate-8-0	passed
restore-to-encrypted-cluster-8-0	passed
scaling-proxysql-8-0	passed
scaling-8-0	passed
scheduled-backup-5-7	passed
scheduled-backup-8-0	passed
security-context-8-0	passed
smart-update1-8-0	passed
smart-update2-8-0	passed
storage-8-0	passed
tls-issue-cert-manager-ref-8-0	passed
tls-issue-cert-manager-8-0	passed
tls-issue-self-8-0	passed
upgrade-consistency-8-0	passed
upgrade-haproxy-5-7	passed
upgrade-haproxy-8-0	passed
upgrade-proxysql-5-7	passed
upgrade-proxysql-8-0	passed
users-5-7	passed
users-8-0	passed
validation-hook-8-0	passed
We run 41 out of 41

commit: https://github.com/percona/percona-xtradb-cluster-operator/pull/1637/commits/bcd9e9a69468449f2a5ff2782718d69efdab0ec3 image: perconalab/percona-xtradb-cluster-operator:PR-1637-bcd9e9a6