“Curl error 56: Recv failure: Connection was reset“ connection error occurs arbitrarily when using UnityWebRequest.SendWebRequest

Reproduction steps:
1. Open the “CurlErrorStripped.zip” project
2. Open Test Runner and click “PlayMode”
3. Run the “UnityRestOperatorTests” test a few times

Expected result: The test passes every time
Actual result: The test fails sometimes with “Curl error 56: Recv failure: Connection was reset“ in Console

Reproduced in: 2021.3.23f1, 2023.1.0b13, 2023.2.0a11
Could not test in: 2020.3.47f1, 2022.2.16f1 (dependency errors)

Reproduced using: Windows 10 (by reporter), Windows 11
Not reproduced using: macOS 13.2.1 (Intel)

Notes:
1. Test fails more often in 2021.3 (~50%) than in 2023.2 (~10%)
2. Also reproduced in a test Player