[fix](Export) Cancel the export job when the ring buffer have no enough slot

[BePPPower]

Problem Summary:

If there happen exceptions in addMemoryTask, we must update the state of the export job to CANCELLED because we have added this export job in ExportMgr.

Check List (For Author)

• Test

  • Regression test
  • Unit Test
  • Manual test (add detailed scripts or steps below)
  • No need to test or manual test. Explain why:
    • This is a refactor/code format and no logic has been changed.
    • Previous test can cover this change.
    • No code files have been changed.
    • Other reason

• Behavior changed:

  • No.
  • Yes.

• Does this need documentation?

  • No.
  • Yes.

Check List (For Reviewer who merge this PR)

• Confirm the release note
• Confirm test cases
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• Add branch pick label

[doris-robot]

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4. Which code was refactored and why was this part of the code refactored?
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[morningman]

LGTM

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[github-actions]

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[morningman]

run buildall