feat: add support for container lifecycle hooks

[Helinanu]

Requirements

• [ ] I have added test coverage for new or changed functionality <- partially
• [x] I have followed the repository's pull request submission guidelines
• [x] I have validated my changes against all supported platform versions

Related issues

https://github.com/launchdarkly/ld-relay-helm/issues/56

Describe the solution you've provided

A simple addition to enable including lifecycle hooks to relay deployment.

Describe alternatives you've considered

Not that much alternatives to this one in my opinion

Additional context

[keelerm84]

Thank you for this contribution!