proxy fix wake compute console retry

[conradludgate]

Problem

1. Proxy is retrying errors from cplane that shouldn't be retried
2. Proxy is not using the retry_after_ms value

Summary of changes

1. Correct the could_retry impl for ConsoleError.
2. Update could_retry interface to support returning a fixed wait duration.

Checklist before requesting a review

• I have performed a self-review of my code.
• If it is a core feature, I have added thorough tests.
• Do we need to implement analytics? if so did you add the relevant metrics to the dashboard?
• If this PR requires public announcement, mark it with /release-notes label and add several sentences in this section.

Checklist before merging

• Do not forget to reformat commit message to not include the above checklist

[github-actions]

2910 tests run: 2793 passed, 0 failed, 117 skipped (full report)

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Flaky tests (1)

Postgres 14

• test_subscriber_restart: release

Code coverage* (full report)

• functions: 32.7% (6870 of 20995 functions)
• lines: 50.2% (53649 of 106917 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
b224bd0 at 2024-06-25T17:55:34.753Z :recycle:}