add singler python implementation

[dariarom94]

Describe your changes

Checklist before requesting a review

• I have performed a self-review of my code

• Check the correct box. Does this PR contain:

  • Breaking changes
  • New functionality
  • Major changes
  • Minor changes
  • Bug fixes

• Proposed changes are described in the CHANGELOG.md

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[LouisK92]

Added a few comments in the code. But component looks almost perfect now.

To include the method also into the pipeline there are a few files that need small adjustments:

1. workflow configuration

task_ist_preprocessing/src/workflows/run_benchmark/config.vsh.yaml

• line 101: add singler to default: "ssam:tacco:moscot:mapmycells:tangram"
• line 172: add singler to dependencies

2. workflow file

task_ist_preprocessing/src/workflows/run_benchmark/main.nf

• line 379: add singler to ct annotation methods

3. script to run the benchmark

task_ist_preprocessing/scripts/run_benchmark/*.sh
In each script add singler to the celltype_annotation_methods (comment it out if most other methods are commented out)