[FIX] fix bugs in mot_param_search.py

[dzambrano]

This PR solves bugs for mot_param_search.py following #265 and #266.

[codecov]

Codecov Report

Merging #270 (e8a78b4) into master (ec7a2e3) will decrease coverage by 0.53%.
The diff coverage is n/a.

❗ Current head e8a78b4 differs from pull request most recent head d66b463. Consider uploading reports for the commit d66b463 to get more accurate results

@@            Coverage Diff             @@
##           master     #270      +/-   ##
==========================================
- Coverage   69.24%   68.70%   -0.54%     
==========================================
  Files          92       92              
  Lines        4659     4627      -32     
  Branches      897      897              
==========================================
- Hits         3226     3179      -47     
- Misses       1148     1160      +12     
- Partials      285      288       +3     

Flag	Coverage Δ
unittests	68.68% <ø> (-0.50%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
mmtrack/models/mot/base.py	36.66% <0.00%> (-4.58%)	⬇️
mmtrack/datasets/sot_train_dataset.py	81.81% <0.00%> (-4.05%)	⬇️
mmtrack/datasets/pipelines/transforms.py	84.68% <0.00%> (-3.44%)	⬇️
mmtrack/models/sot/base.py	44.21% <0.00%> (-2.79%)	⬇️
mmtrack/models/losses/l2_loss.py	18.03% <0.00%> (-2.61%)	⬇️
mmtrack/models/vid/base.py	38.59% <0.00%> (-2.09%)	⬇️
mmtrack/models/mot/tracktor.py	56.06% <0.00%> (-1.30%)	⬇️
mmtrack/models/mot/trackers/base_tracker.py	84.12% <0.00%> (-0.61%)	⬇️
mmtrack/models/reid/base_reid.py	86.36% <0.00%> (-0.60%)	⬇️
mmtrack/models/reid/fc_module.py	83.87% <0.00%> (-0.51%)	⬇️
... and 3 more

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[OpenMMLab-Coodinator]

Hi @dzambrano ！First of all, we want to express our gratitude for your significant PR in this project. Your contribution is highly appreciated, and we are grateful for your efforts in helping improve this open-source project during your personal time. We believe that many developers will benefit from your PR.

We would also like to invite you to join our Special Interest Group (SIG) private channel on Discord, where you can share your experiences, ideas, and build connections with like-minded peers. To join the SIG channel, simply message moderator— OpenMMLab on Discord or briefly share your open-source contributions in the #introductions channel and we will assist you. Look forward to seeing you there! Join us ：https://discord.gg/raweFPmdzG

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Thank you again for your contribution❤