Indicate missing required event subscriptions and missing required permission

[retog]

Is your feature request related to a problem? Please describe

Yes. Using nrehwaldt/wuffle@sha256:919bd94b2192a60e5b909b7817773857af19cffb5b1177143f2265f44bd5b193 I'm getting warning messages like this:

WARN (wuffle:github-app): missing required permissions
    installation: "retog"
    permissions: {
      "issues": "write",
      "contents": "read",
      "metadata": "read",
      "pull_requests": "write",
      "repository_hooks": "write",
      "vulnerability_alerts": "read"
    }
WARN (wuffle:github-app): missing required event subscriptions
    installation: "retog"
    events: [
      "issues",
      "issue_comment",
      "label",
      "merge_queue_entry",
      "milestone",
      "public",
      "pull_request",
      "push",
      "repository"
    ]

I don't see what is missing.

Describe the solution you'd like

The error message should list what is missing and provide URL of documentation to learn how to fix.

Describe alternatives you've considered

I've considered an AI powered config wizard using quantum technology.

Describe alternatives you've considered

none.

[nikku]

Please use an existing issue template, providing all necessary details, including how to reproduce this + what version of wuffle you're using, if applicable. I'll not be able to assist you otherwise.

[retog]

Added the labels of the template and completed

[nikku]

Was a quick fix: https://github.com/nikku/wuffle/commit/7e049ff90a915183fef8cbfd62c85d70ffc00447.