RequestHandler: Fix memory leak when setting streaming service

[norihiro]

Description

Replaced OBSService type with OBSServiceAutoRelease in RequestHandler::SetStreamServiceSettings.

Motivation and Context

Memory leaks when setting streaming service using obs-websocket.

How Has This Been Tested?

Tested OS(s): Ubuntu 22.04

Steps to test the memory-leak is as below.

1. Start obs with clean configuration

   export XDG_CONFIG_HOME=$(mktemp -d /dev/shm/obs-XXXXXX)
   obs &

   1. In the wizard, configure Optimize just for recording, I will not be streaming.
2. Enable WebSocket server
   1. also disable password for simple testing.
3. Run these lines in python3

   import obsws_python
   cl = obsws_python.ReqClient(host='localhost', port=4455)
   cl.send('SetStreamServiceSettings', {
      'streamServiceType': 'rtmp_custom',
      'streamServiceSettings': {
          'server': 'rtmp://localhost/live',
          'key': 'secret',
          }})

4. Exit obs

Types of changes

• Bug fix (non-breaking change which fixes an issue)

Checklist:

• [x] I have read the Contributing Guidelines.
• [x] All commit messages are properly formatted and commits squashed where appropriate.
• [x] My code is not on master or a release/* branch.
• [x] The code has been tested.
• [x] I have included updates to all appropriate documentation.

[tt2468]

Are you sure it leaks currently? I very explicitly chose OBSService as there was weird behavior with service reference counting that required it, but don't remember why.

[norihiro]

I've added steps to reproduce in the description of this PR.

Something I noticed weird is that SetStreamServiceSettings at first time will leak the memory but 2nd time and later won't. This is because SetStreamServiceSettings will not re-create the object if the service-type matches.

If you have a doubt for the reference count, how about using obs_service_t * instead of OBSService and intentionally calls obs_service_release?