too many polls exception when calling s3

I'm sometimes getting the exception `Eio_ssl.Exn.Too_many_polls` when posting an image to s3:

```
server_dev.exe: [INFO] ALPN: offering h2
server_dev.exe: [INFO] ALPN: offering http/1.1
server_dev.exe: [INFO] ALPN: offering http/1.0
server_dev.exe: [INFO] SSL connection using TLSv1.2 / ECDHE-RSA-AES128-GCM-SHA256
server_dev.exe: [INFO] Server certificate:
Subject: /CN=*.s3.amazonaws.com
Start Date: Oct 10 00:00:00 2023 GMT
Expiration Date: Jul 3 23:59:59 2024 GMT
Issuer: /C=US/O=Amazon/CN=Amazon RSA 2048 M01
SSL certificate verify result: ok
server_dev.exe: [INFO] ALPN: server agreed to use http/1.1
server_dev.exe: [INFO] Sending request:
PUT /images/3206fd83159026b26db590f5a05b4288.png HTTP/1.1
x-amz-date: 20231027T234649Z
x-amz-content-sha256: UNSIGNED-PAYLOAD
Authorization:
Content-Type: image/png
host:
content-length: 1783006
````