test: Fix flaky *_collection_iterate tests with polling helper
#707
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| 47s | |
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| 1m 12s | |
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| 9s | |
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| 2m 24s | |
| 49s | |
| 13s | |
| 46s | |
| 10s | |
| 13s | |
| 47s | |
| 15s | |
| 2m 14s | |
| 15s | |
| 13s | |
| 1m 9s | |
| 48s | |
| 13s | |
| 12s | |
| 1m 8s | |
| 1m 3s | |
| 1m 14s | |
| 32m 18s |