Suppress storage discrepancy error if external volume autoscaling is enabled

[terryyanko]

CHANGE DESCRIPTION

Problem:
If using an external volume autoscaler for dynamic PVC resizing, the operator continually throws the below error if the volume is scaled beyond its initial spec.

requested storage is less than actual storage

Cause:
The operator is not currently aware of whether or not an external autoscaler is in use

Solution:
Provide an option to allow for external volume autoscaling

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?
• Are all needed new/changed options added to the Helm Chart?
• 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 MongoDB version?
• Does the change support oldest and newest supported Kubernetes version?

[CLAassistant]

All committers have signed the CLA.

[JNKPercona]

Test name	Status
arbiter	passed
balancer	passed
cross-site-sharded	passed
custom-replset-name	passed
custom-tls	passed
custom-users-roles	passed
custom-users-roles-sharded	passed
data-at-rest-encryption	failure
data-sharded	passed
demand-backup	passed
demand-backup-eks-credentials-irsa	passed
demand-backup-fs	passed
demand-backup-incremental	passed
demand-backup-incremental-sharded	passed
demand-backup-physical	passed
demand-backup-physical-sharded	passed
demand-backup-sharded	passed
expose-sharded	passed
finalizer	passed
ignore-labels-annotations	passed
init-deploy	passed
ldap	passed
ldap-tls	passed
limits	passed
liveness	passed
mongod-major-upgrade	passed
mongod-major-upgrade-sharded	passed
monitoring-2-0	passed
multi-cluster-service	passed
multi-storage	failure
non-voting	passed
one-pod	passed
operator-self-healing-chaos	passed
pitr	failure
pitr-physical	passed
pitr-sharded	passed
pitr-physical-backup-source	passed
preinit-updates	passed
pvc-resize	passed
recover-no-primary	passed
replset-overrides	passed
rs-shard-migration	passed
scaling	passed
scheduled-backup	failure
security-context	passed
self-healing-chaos	passed
service-per-pod	passed
serviceless-external-nodes	passed
smart-update	passed
split-horizon	passed
stable-resource-version	passed
storage	passed
tls-issue-cert-manager	passed
upgrade	passed
upgrade-consistency	passed
upgrade-consistency-sharded-tls	failure
upgrade-sharded	passed
users	passed
version-service	passed
We run 59 out of 59

commit: ea494d1
image: perconalab/percona-server-mongodb-operator:PR-1897-ea494d1c