[Keras 3 OpenVINO Backend]: Support numpy.flip operation

[Imokutmfon]

implementation for numpy.flip using openvino ops

please review @rkazants

Fixes openvinotoolkit/openvino#29359

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 80.00000% with 4 lines in your changes missing coverage. Please review.

Project coverage is 82.72%. Comparing base (9205298) to head (f85f034).
Report is 3 commits behind head on master.

Files with missing lines	Patch %	Lines
keras/src/backend/openvino/numpy.py	80.00%	2 Missing and 2 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #21410      +/-   ##
==========================================
+ Coverage   82.67%   82.72%   +0.05%     
==========================================
  Files         565      565              
  Lines       55073    55239     +166     
  Branches     8571     8612      +41     
==========================================
+ Hits        45532    45698     +166     
+ Misses       7443     7429      -14     
- Partials     2098     2112      +14     

Flag	Coverage Δ
keras	82.53% <80.00%> (+0.05%)	⬆️
keras-jax	63.31% <0.00%> (-0.20%)	⬇️
keras-numpy	58.50% <0.00%> (-0.18%)	⬇️
keras-openvino	33.81% <80.00%> (+0.35%)	⬆️
keras-tensorflow	63.72% <0.00%> (-0.20%)	⬇️
keras-torch	63.35% <0.00%> (-0.20%)	⬇️

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