[source-mysql] : don't emit final state if there is an underlying stream failure

[akashkulk]

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Relevant information

Context : https://airbytehq-team.slack.com/archives/C043JHEEYKG/p1707152897893279

We're seeing failures in source-mysql where :

1. A stream fails
2. State iterator emits final state message (indicating that the snapshot is complete)
3. Airbyte proceeds to perform incremental syncs.

This causes data loss, as 2 should emit an intermediate state message. We've lost all the data since the first failure.

The fix is to change the logic :

1. If a stream snapshot has failed, emit the intermediate message OR fail
2. Throw an exception to prevent the sync from progressing further

This would be inline with how source-mongo & source-postgres deal with these failures. Furthermore, as SourceStateIterator will be used as the base class for emitting state counts for Postgres & Mongo, this behavior should be standardized.

[akashkulk]

This was a regression introduced in version 3.3.1