Add the Topologyspreadconstraints to deployments in Helm Chart

[heyosi]

Proposed changes

I would like to add Topologyspreadconstraint to deployments in the Helm Chart:

topologySpreadConstraints:
- maxSkew: 1
  topologyKey: topology.kubernetes.io/zone
  whenUnsatisfiable: DoNotSchedule
  labelSelector:
    matchExpressions:
    - key: app
      operator: In
      values:
      - {{ template "splunk-kubernetes-metrics.name" . }}

The issue link: 873

Types of changes

What types of changes does your code introduce?

• [ ] Bugfix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist

• [x] I have read the CONTRIBUTING doc
• [x] I have read the CLA
• [x] I have added necessary documentation (if appropriate)
• [x] Any dependent changes have been merged and published in downstream modules