fix: re-download bulk file if an empty temp file exists

[astuteo]

Description

Prevents a zero-byte temp file from blocking re-download of Shopify bulk data.

If a previous attempt left a 0-byte file at $this->tempFilePath, it now gets removed before the existence check, allowing a fresh download.

This resolves cases where the job would hang and constantly recycle "Processing bulk operation data..." in the queue without ever completing the job

[nfourtythree]

Hi @astuteo

Thank you for your PR. Although we haven't seen this issue reported before this certainly would solve the issue that could occur.

Will get this merged and in a upcoming release.

To get this early, change your craftcms/shopify requirement in your project's composer.json to:

"require": {
  "craftcms/shopify": "6.x-dev as 6.1.1",
  "...": "..."
}

Then run composer update.

Thanks!