issue self signed certificate

[nabuskey]

fixes: #137 related to: #300 #293

With this PR, idpbuilder will:

1. Create a self signed certificate.
2. Create a TLS secret in the ingress-nginx NS.
3. Use it as the default TLS certificate for ingress-nginx. (you can still use other certs configured at ingress level)
4. Update ArgoCD's CM to trust the CA.
5. Create a CM that contains cert to the default NS.

I thought about using cert-manager but decided not to use it. For our purposes, we just need a certificate for ingress-nginx for in-cluster and incoming traffic only. Introducing cert-manager means:

1. We need to maintain cert-manager manifests.
2. Slower installation speed. We now need to wait for cert-manager to do its thing and be ready before anything else can continue.
3. Introduces three pods that will do nothing for the most part.

[nabuskey]

I think I'd rather wait for concrete use cases for cert-manager until we pull it into core. Ready for another round of review.

[jessesanford]

I agree on waiting for more use cases before bringing in cert manager. It should be reasonably easy to roll forward to it when the time comes.

[cmoulliard]

I think I'd rather wait for concrete use cases for cert-manager until we pull it into core. Ready for another round of review.

Cert Manager can help to deal with many use cases like:

• Generate Self Signed Certificate for the platform where it runs: https://cert-manager.io/docs/configuration/selfsigned/
• Inject OOTB the TLS Secret within the ingress resources - https://cert-manager.io/docs/usage/ingress/
• Trust Certificates issued for domains: LetsEncrypt, etc - https://cert-manager.io/docs/configuration/acme/
• Distribute certifcates as bundle: https://cert-manager.io/docs/trust/trust-manager/
• Create HTTPS/TLS Cert/Key for runtime applications, Java, etc) - https://github.com/snowdrop/pki?tab=readme-ov-file#create-a-pkcs12-using-cert-manager