libs/proxy: Add missing waker wake in poll_shutdown

[cloneable]

Problem

poll_shutdown() returns Poll::Pending but does not trigger a wake and callers seems to rely on this.

Summary of changes

Add a wake_by_ref().

[conradludgate]

https://github.com/neondatabase/rust-postgres/blob/00940fcdb57a8e99e805297b75839e7c4c7b1796/tokio-postgres/src/connection.rs#L300 would be good to check if upstream tokio-postgres still has this same issue

[conradludgate]

On second look, this might be correct before. poll_read/poll_write will wake when ready.

[cloneable]

Yes. Must not be happening often.
https://github.com/sfackler/rust-postgres/blob/d7ccc7e398755addf13096b55bdab49c2cc96156/tokio-postgres/src/connection.rs#L277-L279

[cloneable]

We can look at this once you're back. I'll mark this PR as draft until we know more.

[github-actions]

7095 tests run: 6796 passed, 0 failed, 299 skipped (full report)

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Flaky tests (3)

Postgres 17

• test_compute_pageserver_connection_stress: debug-x86-64

Postgres 16

• test_physical_replication_config_mismatch_max_locks_per_transaction: release-arm64

Postgres 15

• test_physical_replication_config_mismatch_max_locks_per_transaction: release-x86-64

Code coverage* (full report)

• functions: 31.2% (8397 of 26876 functions)
• lines: 48.0% (66660 of 139016 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
33166ea at 2024-12-19T17:14:40.294Z :recycle:}