fix(test_remote_storage_upload_queue_retries): became flakier since #6960

[problame]

This PR increases the wait_until timeout.
These are where things became more flaky as of #6960.
Most likely because it doubles the work in the
churn_while_failpoints_active_thread.

Slack context: https://neondb.slack.com/archives/C033RQ5SPDH/p1709554455962959?thread_ts=1709286362.850549&cid=C033RQ5SPDH

[github-actions]

2484 tests run: 2362 passed, 0 failed, 122 skipped (full report)

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Flaky tests (2)

Postgres 16

• test_wal_restore: release
• test_wal_restore_initdb: release

Code coverage* (full report)

• functions: 28.7% (6937 of 24179 functions)
• lines: 47.2% (42540 of 90144 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
708a7a4 at 2024-03-04T13:13:49.547Z :recycle:}