RetryProxyHandler should stop retrying when invocation result fails

[satvu]

Sub-problem identified while investigating #10936. When ScriptInvocationResult fails, we should stop trying to proxy the HttpRequest tied to the invocation.

Example of this repro in #10580:

[2024-10-30T03:18:47.651Z] A function timeout has occurred. Restarting worker process executing invocationId '6d2f2ee4-d1d4-4910-9821-b48986e8e3f9'.
[2024-10-30T03:18:48.032Z] 0: 32 (PID: 7404)
[2024-10-30T03:18:48.213Z] Worker process started and initialized.
[2024-10-30T03:18:48.579Z] 1: 13 (PID: 7404)
[2024-10-30T03:18:49.033Z] 0: 33 (PID: 7404)
...
[2024-10-30T03:18:52.063Z] 0: 36 (PID: 7404)
[2024-10-30T03:18:52.617Z] 1: 17 (PID: 7404)
[2024-10-30T03:18:52.686Z] Failed to proxy request to the worker. Retrying in 50ms. Attempt 1 of 3.
[2024-10-30T03:18:52.686Z] Failed to proxy request to the worker. Retrying in 50ms. Attempt 1 of 3.
[2024-10-30T03:18:56.798Z] Failed to proxy request to the worker. Retrying in 100ms. Attempt 2 of 3.
[2024-10-30T03:18:56.798Z] Failed to proxy request to the worker. Retrying in 100ms. Attempt 2 of 3.