feat(argo-workflows): check prometheus CRD for ServiceMonitor

[cmontemuino]

ServiceMonitor resource should not be rendered unless Prometheus CRDs are available.

This changeset includes an extra option to override the apiVersion Prometheus provides.

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How to test

1 - ServiceMonitor is NOT rendered if Prometheus CRDs are not available

helm template --set controller.metricsConfig.enabled=true,controller.serviceMonitor.enabled=true charts/argo-workflows

2 - ServiceMonitor IS rendered when Prometheus CRDs are available

helm template --api-versions "monitoring.coreos.com/v1" --set controller.metricsConfig.enabled=true,controller.serviceMonitor.enabled=true charts/argo-workflows

3 - ServiceMonitor is NOT rendered if overriding Prometheus apiVersion and it's not available

helm template --api-versions "monitoring.coreos.com/v1" --set controller.metricsConfig.enabled=true,controller.serviceMonitor.enabled=true,controller.serviceMonitor.apiVersion="monitoring.coreos.com/v2" charts/argo-workflows

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close #2427

Checklist:

• [x] I have bumped the chart version according to versioning
• [x] I have updated the documentation according to documentation
• [x] I have updated the chart changelog with all the changes that come with this pull request according to changelog.
• [x] Any new values are backwards compatible and/or have sensible default.
• [x] I have signed off all my commits as required by DCO.
• [ ] My build is green (troubleshooting builds).