Remove tracker and tracker_worker

[sondreso]

Issue Resolves #my_issue

Approach Short description of the approach

(Screenshot of new behavior in GUI if applicable)

Pre review checklist

• [ ] Read through the code changes carefully after finishing work
• [ ] Make sure tests pass locally (after every commit!)
• [ ] Prepare changes in small commits for more convenient review (optional)
• [ ] PR title captures the intent of the changes, and is fitting for release notes.
• [ ] Updated documentation
• [ ] Ensured that unit tests are added for all new behavior (See Ground Rules), and changes to existing code have good test coverage.

Pre merge checklist

• [ ] Added appropriate release note label
• [ ] Commit history is consistent and clean, in line with the contribution guidelines.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 80.79470% with 29 lines in your changes are missing coverage. Please review.

Project coverage is 85.76%. Comparing base (ea34ecc) to head (4fad2f9).

Files	Patch %	Lines
src/ert/run_models/base_run_model.py	73.95%	25 Missing :warning:
src/ert/gui/simulation/queue_emitter.py	62.50%	3 Missing :warning:
src/ert/cli/main.py	87.50%	1 Missing :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6811      +/-   ##
==========================================
+ Coverage   85.74%   85.76%   +0.01%     
==========================================
  Files         383      382       -1     
  Lines       23266    23241      -25     
  Branches      893      877      -16     
==========================================
- Hits        19950    19932      -18     
+ Misses       3206     3196      -10     
- Partials      110      113       +3     

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[oyvindeide]

A very non-scientific test, but test_cli.py was 30% faster in this branch vs main

[xjules]

Would it be realistic to make the monitor.py fully async? Not at the least to get rid of the duplexer. ~~Update: I have a Monitor_async.py version in my PR: https://github.com/equinor/ert/pull/6994~~ I've managed to go without in that PR but still have a version available.