Schedule image layer uploads in tiered compaction

[arpad-m]

Tiered compaction hasn't scheduled the upload of image layers. In the test_gc_feedback.py test this has caused warnings like with tiered compaction:

INFO request[...] Deleting layer [...] not found in latest_files list, never uploaded?

Which caused errors like:

ERROR layer_delete[...] was unlinked but was not dangling

Fixes #7244

[github-actions]

2748 tests run: 2608 passed, 0 failed, 140 skipped (full report)

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Code coverage* (full report)

• functions: 28.3% (6361 of 22503 functions)
• lines: 47.2% (44883 of 95142 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
9b42ad5 at 2024-03-30T00:49:28.636Z :recycle:}

[koivunej]

Aah, apologies for missing the lack of upload in the first place. I am glad I added the nagging messages :)