Update 2020_Margaryan_Viking: update dates in SSF

[TCLamnidis]

Changed the date formatting in the SSF to YYYY-MM-DD.

Also: The old ssf validator did not validate the formatting of these columns, but the new one does. So this problem should not happen again.

Closes #24

PR Checklist

• Add the appropriate label to your PR (new package or package update).
• The PR title is in the format Add/update package: {package_name}.
• The PR description includes a link to the issue requesting the package its
  update. (Add to Closes #XXX above.)

If adding or updating a package:

• This PR contains a sequencingSourceFile (.ssf) for the requested
  package.
• The name of the .ssf file(s) matches the package name (i.e.
  packages/2023_my_package/2023_my_package.ssf).
• Comment @delphis-bot create recipe to this pull request to awaken
  Poseidon's trusty helper. (This should be repeated whenever changes are
  made to the SSF file contents).

Delphis-bot will then add a number of files to the PR. Check that they are all
there:

• The file packages/{package_name}/{package_name}.tsv was added to the PR.
• The file packages/{package_name}/{package_name}.tsv_patch.sh was added
  to the PR from template.
• The file packages/{package_name}/script_versions.txt was added to the
  PR.
• The file packages/{package_name}/{package_name}.config was added to the
  PR from template.

Human validation

Package SSF file (*.ssf)

• I confirm that the poseidon_IDs, udg, and library_built are filled
  and correct.
• I made sure to leave notes where necessary to explain any special
  cases/judgement calls made for data entries.

Package TSV file (*.tsv)

• I confirm that the UDG, Strandedness columns are correct for each
  library.
• I confirm that the R1_target_file and R2_target_file columns point to
  the correct FastQ files for the library (i.e. consistent with SSF file).

Package config file (*.config)

The template config file includes a few TODO statements, and information about
them. Please ensure that you:

• I have selected the appropriate config for the CaptureType of the package.
• If any nf-core/eager parameters need to be altered from their defaults, I
  have added them within the params section at the end of the package
  config file.

[TCLamnidis]

@delphis-bot create recipe

[TCLamnidis]

The new recipe makes no changes to the eager TSV or script_versions files, as no information has changed.

[TCLamnidis]

reprocessing triggered for consistency in config profiles etc.