Integrate breez-sdk-swift release pipeline into main repo CI

[cnixbtc]

Back when this repo and its release workflow was setup, we didn't have the CI setup in the main repo that we now have. Therefore, we built the workflow to release a new version of the Swift package and CocoaPod as part of the breez-sdk-swift repo.

This, however, requires us to manually trigger a release here before we do a run of the main repo's release pipeline. We could now streamline this process, and move the pipeline for releasing the Swift package and CocoaPod into the main repo's CI workflow.

[JssDWt]

I got started on that here a while back. breez/breez-sdk-greenlight#620
I got a bit stuck thinking about how to publish swift before publishing react native, but only if both are published... I can have another look at that PR soon.