Enable attaching sample sheet to landing requests

[mvdbeek]

Both for data landing and workflow landing requests

How to test the changes?

(Select all options that apply)

• I've included appropriate automated tests.
• This is a refactoring of components with existing test coverage.
• Instructions for manual testing are as follows:
  1. [add testing steps and prerequisites here if you didn't write automated tests covering all your changes]

License

• I agree to license these and all my past contributions to the core galaxy codebase under the MIT license.

[jmchilton]

I'm not opposed to any of this and I do appreciate you getting it to work - I think maybe I wish the validation felt more holistic. Like I assume we're not validating collection_type any of those places and we're not validating record types (if there is record type validation code anywhere). But I can create an issue to revisit this and clean it up if I'm unhappy with it - I know you're in a hurry and you've done way more work than you expected to get it working and I really appreciate all of that.

[mvdbeek]

I can work on the validation, I agree that's just as important as the functionality. I think feature-wise we're probably good for the planned demo in January, so there's no particular rush ... I can always deploy from a branch for test.galaxyproject.org