Check existence of export file with request before resuming sync

[dmosorast]

Description of change

It appears that there's a situation where Marketo marks an export as "Completed", but returns a 404 when requesting the file itself. This is an error scenario as far as the tap is concerned.

This PR adjusts the tap's behavior when resuming to check for a 404 when requesting a 0 byte range of the file, and reporting it to the sync code as not existing if that check returns a 404.

Manual QA steps

• Ran through a situation with a bookmarked file ID that didn't exist, and ensured it started a new sync.
• Ran through a new sync and ensured that the records were requested and emitted properly
• Ran through end to end with the current code to ensure that it still works

Risks

• Low, currently the tap will just keep persisting the same state when a bunk export_id gets in there.

Rollback steps

• revert this branch, bump patch version, release new version