workflows: harvesting description arXiv link

Signed-off-by: Georgios Papoutsakis <georgios.papoutsakis@cern.ch>
workflows: blocks in styles templates

* Adds blocks and base template for workflow styles templates.

Signed-off-by: Jan Aage Lavik <jan.age.lavik@cern.ch>
workflows: attached files improvement

* Amends a bit how the "files" task result integrates to show
  any uploaded files in Holding Pen detailed view.

Co-authored-by: Jan Aage Lavik <jan.age.lavik@cern.ch>
Signed-off-by: Georgios Papoutsakis <georgios.papoutsakis@cern.ch>
workflows: styles fixes

Signed-off-by: Georgios Papoutsakis <georgios.papoutsakis@cern.ch>
workflows: error signal catching
workflows: indentation from 4 to 2 spaces

* Updates indentation from 4 to 2 spaces across all templates in
  the module.

Reported-by: Jiri Kuncar <jiri.kuncar@cern.ch>
Signed-off-by: Jan Aage Lavik <jan.age.lavik@cern.ch>