[1.6.x] Fix export precision

[sovrasov]

Summary

This PR fixes low precision (fp16) for in default export mode (fp32)

[codecov]

Codecov Report

Attention: Patch coverage is 71.42857% with 2 lines in your changes are missing coverage. Please review.

Project coverage is 80.73%. Comparing base (0192d26) to head (65f3d5e).

Files	Patch %	Lines
...otx/algorithms/segmentation/adapters/mmseg/task.py	0.00%	2 Missing ⚠️

Additional details and impacted files

@@                Coverage Diff                 @@
##           releases/1.6.0    #3394      +/-   ##
==================================================
- Coverage           80.74%   80.73%   -0.02%     
==================================================
  Files                 536      536              
  Lines               40488    40491       +3     
==================================================
- Hits                32694    32691       -3     
- Misses               7794     7800       +6     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.