Clean-up of enkf_node

[dafeda]

Pre review checklist

• Added appropriate release note label
• PR title captures the intent of the changes, and is fitting for release notes.
• Commit history is consistent and clean, in line with the contribution guidelines.

Adding labels helps the maintainers when writing release notes. This is the list of release note labels.

[codecov-commenter]

Codecov Report

Merging #3926 (15e41a0) into main (4d9ed75) will increase coverage by 20.40%.
The diff coverage is 0.00%.

❗ Current head 15e41a0 differs from pull request most recent head c448118. Consider uploading reports for the commit c448118 to get more accurate results

@@             Coverage Diff             @@
##             main    #3926       +/-   ##
===========================================
+ Coverage   38.24%   58.64%   +20.40%     
===========================================
  Files         132      545      +413     
  Lines       18432    41409    +22977     
  Branches     3765     3762        -3     
===========================================
+ Hits         7049    24284    +17235     
- Misses      10382    16124     +5742     
  Partials     1001     1001               

Impacted Files	Coverage Δ
src/clib/lib/enkf/enkf_node.cpp	33.66% <0.00%> (+2.66%)	⬆️
src/ert/shared/cli/workflow.py	66.66% <0.00%> (ø)
src/ert/gui/gert_main.py	95.65% <0.00%> (ø)
src/ert/_c_wrappers/util/path_format.py	95.83% <0.00%> (ø)
src/ert/shared/plugins/plugin_response.py	100.00% <0.00%> (ø)
...valuator/narratives/monitor_successful_ensemble.py	100.00% <0.00%> (ø)
src/ert/_c_wrappers/fm/ecl/script.py	20.00% <0.00%> (ø)
src/ert/_c_wrappers/fm/rms/rms_config.py	100.00% <0.00%> (ø)
...rc/ert/shared/models/multiple_data_assimilation.py	95.34% <0.00%> (ø)
... and 405 more

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[eivindjahren]

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