Fix ocean encoding for CY49r2/CY50r1

[dsarmany]

Description

Contributor Declaration

By opening this pull request, I affirm the following:

• All authors agree to the Contributor License Agreement.
• The code follows the project's coding standards.
• I have performed self-review and added comments where needed.
• I have added or updated tests to verify that my changes are effective and functional.
• I have run all existing tests and confirmed they pass.

🌈🌦️📖🚧 Documentation 🚧📖🌦️🌈
https://sites.ecmwf.int/docs/dev-section/multio/pull-requests/PR-234

[codecov-commenter]

Codecov Report

❌ Patch coverage is 31.37255% with 35 lines in your changes missing coverage. Please review.
✅ Project coverage is 57.83%. Comparing base (e086b68) to head (b5982e6).
⚠️ Report is 10 commits behind head on develop.

Files with missing lines	Patch %	Lines
src/multio/action/encode/GribEncoder.cc	32.00%	34 Missing ⚠️
src/multio/action/encode/Encode.cc	0.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #234      +/-   ##
===========================================
- Coverage    57.88%   57.83%   -0.06%     
===========================================
  Files          319      319              
  Lines        20533    20578      +45     
  Branches      1595     1600       +5     
===========================================
+ Hits         11886    11901      +15     
- Misses        8647     8677      +30     

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