[Bug] Replace mem leaking torch gaussian_blur in augmentations

[felixdittrich92]

This PR:

• Replace mem leaking GaussianBlur augmentation and the functional used F.gaussian_blur with scipy
• Add corresponding test for own GaussianBlur implementation
• Adjust sigma range

Any feedback is welcome 🤗

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.59%. Comparing base (48873e0) to head (f9cadb7).
Report is 3 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1822      +/-   ##
==========================================
- Coverage   96.60%   96.59%   -0.01%     
==========================================
  Files         165      165              
  Lines        7929     7939      +10     
==========================================
+ Hits         7660     7669       +9     
- Misses        269      270       +1     

Flag	Coverage Δ
unittests	96.59% <100.00%> (-0.01%)	⬇️

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

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