Add a new hook designated for additions to PATH for forward models.

[berland]

Issue Resolves #8967

Approach ➕

• [x] PR title captures the intent of the changes, and is fitting for release notes.
• [x] Added appropriate release note label
• [x] Commit history is consistent and clean, in line with the contribution guidelines.
• [x] Make sure unit tests pass locally after every commit (git rebase -i main --exec 'pytest tests/ert/unit_tests -n logical -m "not integration_test"')

When applicable

• [ ] When there are user facing changes: Updated documentation
• [x] New behavior or changes to existing untested code: Ensured that unit tests are added (See Ground Rules).
• [ ] Large PR: Prepare changes in small commits for more convenient review
• [ ] Bug fix: Add regression test for the bug
• [ ] Bug fix: Create Backport PR to latest release

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 91.58%. Comparing base (45b9a36) to head (045535d).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #8981      +/-   ##
==========================================
+ Coverage   91.57%   91.58%   +0.01%     
==========================================
  Files         345      345              
  Lines       21302    21318      +16     
==========================================
+ Hits        19507    19525      +18     
+ Misses       1795     1793       -2     

Flag	Coverage Δ
cli-tests	39.71% <29.41%> (-0.01%)	:arrow_down:
gui-tests	73.50% <29.41%> (-0.01%)	:arrow_down:
performance-tests	50.25% <29.41%> (-0.02%)	:arrow_down:
unit-tests	80.34% <100.00%> (+0.01%)	:arrow_up:

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[berland]

Closing as there is a better alternative.