Add showErrorStrategy config option for submission form

[strawburster]

Config option submission.showErrorStrategy is of type ShowErrorStrategy, which can be 'onblur' or 'onload'. The default is 'onblur', which will show errors only after clicking an input field.

This PR was provided by The Library Code with the support of FHNW.

References

Description

This PR adds a config option for submission forms to show validation errors on form load. The default strategy, 'onblur', is kept consistent with current behavior.

Instructions for Reviewers

List of changes in this PR:

• Add new submission config option 'showErrorStrategy'
• Use submission config option in src/app/submission/form/submission-form.component.ts

Add the option to the config/config.yml, and test to see that form errors are displayed on form load, not on form input field blur.

rest:
  ssl: true
  host: sandbox.dspace.org
  port: 443
  nameSpace: /server
submission:
  showErrorStrategy: 'onload'

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