Add rate limiter for partial uploads

[petuhovskiy]

Too many concurrect partial uploads can hurt disk performance, this commit adds a limiter.

Context: https://neondb.slack.com/archives/C04KGFVUWUQ/p1719489018814669?thread_ts=1719440183.134739&cid=C04KGFVUWUQ

[github-actions]

2940 tests run: 2823 passed, 0 failed, 117 skipped (full report)

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Flaky tests (1)

Postgres 14

• test_timeline_size_quota_on_startup: release

Code coverage* (full report)

• functions: 32.7% (6909 of 21120 functions)
• lines: 50.1% (54149 of 108105 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
81cfbe7 at 2024-06-28T15:22:13.310Z :recycle:}