fix: parallel release creation with Keygen publisher

[ezekg]

Looks like the previous changes for the Keygen publisher (moving from v1.0 to v1.1 of Keygen's API) contained a bug that slipped through the cracks, as far as automated tests go. I didn't do any manual tests, so this wasn't caught.

Under a normal publish, electron-builder will upload multiple artifacts. The Keygen publisher has a find-or-create method for creating a new release bucket, before uploading artifacts. What I didn't account for in #6941 was that electron-builder uploads these artifacts in parallel, so the find-or-create method isn't as robust as it needed to be.

This results in electron-builder trying to create the same release n times in parallel (n = number of artifacts to upload), causing all but 1 of the release creation requests to fail due to conflict errors.

This results in a failed publish for all users using the Keygen provider and electron-builder v23.3.0.

This wasn't caught in tests because the test for the Keygen publisher only uploaded a single artifact, so a conflict will never occur. That test has been modified to upload multiple artifacts, rather than a single artifact.

This PR resolves the issue by making an additional fetch if a conflict error is encountered.

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🦋 Changeset detected

Latest commit: f03a4fc

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 8 packages

Name	Type
app-builder-lib	Patch
dmg-builder	Patch
electron-builder-squirrel-windows	Patch
electron-builder	Patch
electron-forge-maker-appimage	Patch
electron-forge-maker-nsis-web	Patch
electron-forge-maker-nsis	Patch
electron-forge-maker-snap	Patch

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[ezekg]

As an aside — as @mmaietta and I briefly discussed here, this may be a good indication that before/after hooks are needed for publishers. It'd be much nicer to be able to tell electron-builder to create the release before uploading any artifacts, then publish the release after uploading all artifacts. This would alleviate any need for this find-or-create method.

IMO, somehow allowing publishers to define before/after hooks seems like a good solution here.

[mmaietta]

this may be a good indication that before/after hooks are needed for publishers. It'd be much nicer to be able to tell electron-builder to create the release before uploading any artifacts, then publish the release after uploading all artifacts. This would alleviate any need for this find-or-create method.

I'm in full agreement of this approach as well.