Try fixing IPN flakiness

[Resonious]

We got a bug report about webhooks getting dropped after automatic updates. I noticed that we're not following the official advice on hooks within gateway initializers, which might be the cause. This PR moves the API action registration outside of the gateway initialization code. Hopefully this fixes the issue.

I had a hard time reproducing the original issue, but I was able to confirm that this change doesn't break regular webhook processing.

[FTLam11]

@Resonious Just heads up I'm investigating one cypress admin test it lets me change the KOMOJU endpoint that keeps failing in CI. The test is passing on master when I run on my machine with the same node, cypress, and browser versions though... 😢

[Resonious]

Thanks for the heads up 🙏

[Resonious]

Strange. I can see in the screenshot that it is "waiting for page to load" when the page is quite clearly loaded.

[CicadaMikoto]

Not related to this issue, per se, but I noticed that that screenshot has some keys in it. Are those dev-only keys or are they publicly usable?

[Resonious]

@CicadaMikoto Yes, no worries. It's for a test mode account. You can annoy us by using the keys but can't cause damage. I appreciate the concern!

[CicadaMikoto]

Glad to hear it! I went ahead and submitted it on the VDP, just in case. Glad it's not a big impact.