Clarify release event trigger behaviour

[foosel]

Why:

As it turns out, the release event will not trigger with prereleased type for pre releases getting published from drafts, only with published. This adds a little note to clarify this behaviour.

Closes #5767

What's being changed:

I've added a small note:

Note: The prereleased type will not trigger for pre releases getting published from draft releases. The published type however will. If you want a workflow to run when stable and pre releases are published, subscribe to published instead of released and prereleased.

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[skedwards88]

🎉 Thank you for digging into this and for opening a PR to document your findings! I suggested some small wording changes. If this still sounds good to you, I'll get it merged down.

[foosel]

Sounds good to me, I've committed these suggestions!

[skedwards88]

Awesome! I'll get this merged down for you.

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