Add GH application to add new items from all repositories into Flagsmith Engineering project

In order to have the [Flagsmith Engineering project](https://github.com/orgs/Flagsmith/projects/22/views/2) be the most effective, I want to have all new issues created in all repositories added to it.

As far as I understand it, we have 2 options for doing this:

1. Add a workflow in all of the repositories that we want to implement this for
2. Build an application to listen to GH webhooks, and call the GH API to add new issues (filtered for the relevant repositories as needed) to add them to the project

There is a working example of option (1) in the flagsmith-python-client repository [here](https://github.com/Flagsmith/flagsmith-python-client/blob/main/.github/workflows/add-issues-to-engineering-project.yml), but this is definitely the least DRY option.