[IMPROVE] Remove show message in main thread preference

[reinaldonetof]

Proposed changes

This PR https://github.com/RocketChat/Rocket.Chat/pull/26002 introduced a breaking change in Rocket Chat server 5.0.0. You can see the behavioral differences in the PR

Now there are three behavior options Gifs copied from the PR Default: it unchecks after sending the first message

Always: stay checked for all messages, but the user can unchecked.

Never: stay unchecked for all messages, but the user can check it.

The tests are running correctly for servers < 5.0.0. If your server is >= 5.0.0, please change the configuration to "default"

Issue(s)

How to test or reproduce

Screenshots

Types of changes

• [ ] Bugfix (non-breaking change which fixes an issue)
• [x] Improvement (non-breaking change which improves a current function)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Documentation update (if none of the other choices apply)

Checklist

• [x] I have read the CONTRIBUTING doc
• [x] I have signed the CLA
• [x] Lint and unit tests pass locally with my changes
• [ ] I have added tests that prove my fix is effective or that my feature works (if applicable)
• [ ] I have added necessary documentation (if applicable)
• [ ] Any dependent changes have been merged and published in downstream modules

Further comments