fix: Set subject on CA cert used for signing self-signed certs

[jannfis]

Signed-off-by: jannfis jann@mistrust.net

What type of PR is this?

/kind bug

What does this PR do / why we need it:

See redhat-developer/gitops-operator#277

Recent versions of Firefox refuse to process TLS certificates that are signed by an unnamed CA. The Operator uses a CA certificate that's created without a X509 Subject, and thus, Firefox chokes.

For an existing installation, the argocd-tls and argocd-ca secrets must be deleted and reconciled back by the Operator.

Have you updated the necessary documentation?

• Documentation update is required by this PR.
• Documentation has been updated.

Which issue(s) this PR fixes:

Fixes redhat-developer/gitops-operator#277 redhat-developer/gitops-operator#261

How to test changes / Special notes to the reviewer:

• Install a recent version of Firefox (I used 97.0.1 (64-bit), installed via Flatpak)
• Create simple ArgoCD for the Operator to reconcile and to create a new Argo CD instance. If you use route, make sure that .server.route.tls.termination is set to passthrough (or left blank, because passthrough is the default)
• Point Firefox to the Argo CD UI
• Connection should be successful (the unknown certificate message is expected, but should be skippable)

[wtam2018]

LGTM
thanks @jannfis