ConfigurationManager not using correct App.config file

Question

I upgraded our selenium project from .Net 4.7 to .Net 7. I am facing a problem with ConfigurationManager. The configuration manager is pointing at testhost.dll.config instead of App.config (projectname.dll.config). This is what our App.config looks like:

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <appSettings>
    <add key="TestServer" value="" />
    <add key="TestNode" value="111.11.11.11" />
    <add key="TestPort" value="4444" />
    <add key="TestEnvironment" value="Dev" />
    <add key="TestBrowser" value="chrome" />
  </appSettings>
</configuration>

I am new to dot Net. Any help to point it to app.config would be appreciated.