Co-authored-by: Sijie Guo <sijie@apache.org>
Fixes inability to validate self-signed certs from external clients
### Motivation
Currently self-signed certificates can only be used inside of the same cluster as they are labeled with internal dns names without the possibility of appending additional values. Some use-cases require the connection of external clients. This PR aims to allow users add additional dnsNames (IP or domain) to the self-signed certificates.
### Modifications
* Adds the ability to add `dnsNames` to self-signed certificates to any component like so:
```yaml
tls:
enabled: true
proxy:
enabled: true
dnsNames:
- test.example.com
```
### Verifying this change
- [x] Make sure that the change passes the CI checks.