[Bug] Deprecating "factor"

[philouail]

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Seem the "factor" variable: https://github.com/HUPO-PSI/mzTab-M/blob/main/specification_documents/mzTab_format_specification_2_1-M.adoc#6244-study_variable1-n-factors is confusing, and not really used. As we are thinking of implementing a new "group" variable. Maybe deprecating factor would make this even clearer ?

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A clear and concise description of what you want to add or modify. Please try to also add examples (snippets for the tab-separated format, see https://github.com/HUPO-PSI/mzTab-M/blob/main/specification_documents/mzTab_format_specification_2_1-M.adoc#625-sample_processing1-n for reference)

Deprecating the factor variable.

Submitter Tasks

• Provide a pull request (Please add the link)
• Schema: Update mzTab_m_openapi.yml (View File)
• Specification: Update mzTab_format_specification_2_1-M.adoc with an example (View File)
• Example files: if possible, modify an existing or add a new example file (Existing example files)

Maintainer & WG Tasks

• Triage: Assign labels and Milestones to this issue.
• Discuss and review and approve PR.

Next Steps, once we reach an agreement on the changes above:

• Create a downstream issue in the jmzTab-m repo (https://github.com/lifs-tools/jmzTab-m/issues)
• Implement and test changes in jmzTab-M
• Implement changes in R & Python implementations