"Radix" section of INTRODUCTOIN.md lacks description for non-public repos

[antoneskov]

Problem
Current version of webviz deploy radix workflow does not support non-public (i.e. internal or private) repos.

There is need for certain non-trivial manual interventions:

• radixconfig.yaml has to be modified in order to include the following section:

.....
spec:
......
  build:
    secrets:
      - GITHUB_DEPLOY_KEYS

• A pair of SSH keys has to be generated.
  • The public key goes to Github as a Deploy Key
  • The private key goes to Radix/GITHUB_DEPLOY_KEYS when the app is created

Suggestion
Modify "Radix" section of INTRODUCTION.md accordingly. Emphasize that fully automated setup of Radix app for non-public repos is not supported.