Thread Group Iterations getting unexpected warning - Existing CookieManager HTTP Cookie Manager superseded by HTTP Cookie Manager

### Expected behavior

Cookie Manager added for the Thread Group and Cleared on each iteration. Cookie Manager used for all iterations of the thread group.

### Actual behavior

Getting warning of "HTTPSamplerBase: Existing CookieManager HTTP Cookie Manager superseded by HTTP Cookie Manager" for in this example all the http requests except the first iteration but there is only 1 Cookie Manager.

Attached below is a simplified way to reproduce the problem we've seen. There is only one Cookie Manager within the whole jmx in the threadgroup no others at any other levels.

### Steps to reproduce the problem

[cookiemanagerwarningerror2.jmx.zip](https://github.com/user-attachments/files/20406408/cookiemanagerwarningerror2.jmx.zip)

### JMeter Version

5.6.3

### Java Version

openjdk 21.0.7 2025-04-15

### OS Version

macOS Sequoia Version 15.5