Create a GitHub App in Kubeflow Org for Label Bot Development

[jlewi]

I think we need to create a new GitHub App to be used for label bot development.
https://developer.github.com/apps/quickstart-guides/setting-up-your-development-environment/#step-2-register-a-new-github-app

The need for a GitHub App for testing is documented here as part of the staging cluster setup
https://github.com/kubeflow/code-intelligence/blob/master/Label_Microservice/docs/set_up_staging_cluster.md#step-2-create-a-testing-github-app

@abcdefgs0324 was using a test application owned by his personal account. I don't have access to that and can't install it on Kubeflow repositories.

Creating this issue to track setting up a GitHub App owned by the Kubeflow organization suitable for development of label bot.

We probably want to have separate apps for prod and dev/testing. This way we can easily guard against bad dev/test code by not installing the dev bot on a repository.

[issue-label-bot]

Issue-Label Bot is automatically applying the label kind/feature to this issue, with a confidence of 0.92. Please mark this comment with 👍 or 👎 to give our bot feedback!

Links: app homepage, dashboard and code for this bot.

[jlewi]

Created the app: kf-label-bot-dev

This is owned by the kubeflow org. Ask one of the kubeflow.org administrators to become an app manager for it.

I had to configure a webhook even though we currently don't plan on using one. So I set it to
https://issue-label-bot-dev-kf.endpoints.issue-label-bot-dev.cloud.goog/label-bot

Installed it on:
kubeflow/code-intelligence
kubeflow/kubeflow
kubeflow/testing

[jlewi]

Generated a secret for the webhook

openssl rand -base64 32 > ~/secrets/kf-label-bot-dev.webhook.secret

Stored in gcs.

gs://issue-label-bot-dev_secrets/kf-label-bot-dev.webhook.secret 

[jlewi]

See: machine-learning-apps/Issue-Label-Bot#57 for the setup of a corresponding front end (to handle the webhooks).

Changed the webhook URL for kf-label-bot-dev to
https://label-bot-dev.mlbot.net