gui/js/updater: Improve error handling (#1617)
gui/js/updater: Improve error handling (#1617)

- Extract #skipUpdate() from #checkForUpdate() so we can reuse it on
  error, not only on timeout.
- Ignore error after skipped/timeout
- Retry on error after 1s
- Skip on ENOENT error (dev-app-update.yml)
- Remove stuff already logged by autoUpdater.logger
- Make skipping reason clearer
cozy-labs/cozy-desktop,cozy-labs/cozy-desktop,cozy-labs/cozy-desktop,cozy-labs/cozy-desktop