Fix/anat fast track derivative

[htwangtw]

Closes #32
Closes #33
Closes #34

Solution: ignore anatomical metrics if anat/ is not present

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 0% with 13 lines in your changes are missing coverage. Please review.

Project coverage is 10.85%. Comparing base (c7b951f) to head (adf5437).

Additional details and impacted files

@@             Coverage Diff             @@
##             main      #35       +/-   ##
===========================================
- Coverage   94.46%   10.85%   -83.62%     
===========================================
  Files           5        8        +3     
  Lines         235      350      +115     
===========================================
- Hits          222       38      -184     
- Misses         13      312      +299     

Files	Coverage Δ
giga_auto_qc/workflow.py	8.10% <0.00%> (-77.61%)	⬇️
giga_auto_qc/tests/test_assessments.py	7.27% <0.00%> (ø)
giga_auto_qc/assessments.py	5.33% <0.00%> (-90.45%)	⬇️

... and 4 files with indirect coverage changes

[htwangtw]

@clarkenj On compute canada you can pull the build of this PR to test it out
apptainer build giga_auto_qc_unstable.simg docker://haotingwang/giga_auto_qc:unstable

[htwangtw]

Request from @clarkenj to be addressed: when supplying anatomical only directory, calculate the anatomical dice
Not addressing this as it turned out to be more complicated than I thought.