chore: drop redundant parameter from sumstat qc step

[project-defiant]

✨ Context

Currently study_id is a required parameter for running the summary_statistics_qc step. This is not ideal, as when running in bulk, we can not specify which study_id should be used to create the qc output path.

🛠 What does this PR implement

• Removal of study_id parameter from the summary_statistics_qc step
• Removal of static /qc_results_ that is appended in the step output

The path to QC should be fully configurable, without it's part being hardcoded.

🙈 Missing

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[DSuveges]

All makes sense. We no longer need a study identifier, the output path is directly given instead of being constructed with studyId.