Update all courses to use workflow-level inputs

[ewels]

We should start using the new syntax parser (currently opt-in with NXF_SYNTAX_PARSER=v2) and the new workflow-level inputs that come with it:

https://www.nextflow.io/docs/latest/workflow.html#workflow-params-def

See also #724

The nf-core adoption roadmap may also be useful for timings, especially for the nf-core course.

• hello_nextflow - Hello nextflow: New workflow inputs + outputs + strict syntax #743
• hello_nf-core
• nextflow_run
• nf4_science
• side_quests
• training_collections
• other