Update Kubernetes manifest deployment example

[ag-adampike]

This PR:

• cleans up the manifest file for the Deployment resource:
  • removes unnecessary version label
  • pins the Connect version for each respective container
  • assigns a name to the listening port on the connect-api container
• removes the superfluous connect-sync port from the Service manifest and targets the named port of the Pod
• updates the manifest file for the Ingress resource
  • refactored to meet v1 spec (Ingress graduated to GA with Kubernetes 1.19, see changelog)
  • adds annotations to to allow the ingress-shim component of cert-manager to create the Certificate resource
  • targets the named port of the Service resource
• renames the cert-manager manifest file for clarity (this file does not install cert-manager on the cluster)
• removes the now-redundant Certificate resource
• refreshes the readme with an expanded description and deployment instructions

To test:

• [x] Install cert-manager on a Kubernetes cluster
• [x] Deploy 1Password Connect according to the instructions in README.md
• [x] Confirm a working Let's Encrypt cert is acquired and installed
• [x] Test 1Password Connect by connecting via HTTPS

I tested on GCP using GKE Ingress controller.

[ag-adampike]

Hey @volodymyrZotov! would you mind giving this PR a review? 👀

[volodymyrZotov]

Hey @volodymyrZotov! would you mind giving this PR a review? 👀

Hi @ag-adampike. Sure, I'll take a look! Thank you!