Fix accessibility issues with placeholder text in submission forms

[FrancescoMolinaro]

References

Fixes #4198

Description

Following what is described in https://www.deque.com/blog/accessible-forms-the-problem-with-placeholders/ as an issue with placeholder, this PR gives the possibility to disable, via a configuration property, the placeholders in simple fields during submission. (fields where it would just be the replica of the label)

Instructions for Reviewers

If the newly introduced param ignorePlaceholderForSimpleFields is set to true in the default-app.config.ts the placeholders in submission shouldn't be visible unless they are different from the label and bring some additional information.

If set to false all the placeholders should be visible as before.

List of changes in this PR:

Make placeholder presence configurable
Fix wrongly used placeholder in date field

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[tdonohue]

Temporarily closing & reopening this PR to trigger tests to run again. The e2e test failures currently in this PR seem unrelated to the PR itself, and I'm hoping reopening this PR will get this to run against latest main.

[tdonohue]

@FrancescoMolinaro : Just a note this PR seems to be failing the automated accessibility scan that is done in e2e tests. The failure is in the Submission Form and it says this:

1 accessibility violation was detected
[
  {
    id: 'label',
    impact: 'critical',
    description: 'Ensure every form element has a label',
    helpUrl: 'https://dequeuniversity.com/rules/axe/4.10/label?application=axeAPI',
    nodes: 4,
    html: [
      '<input class="form-control ng-untouched ng-pristine ng-valid ng-star-inserted" autocomplete="on" id="6_array-0-dc_contributor_author" name="dc.contributor.author" placeholder="" spellcheck="true" tabindex="0" type="text">',
      '<input class="form-control ng-untouched ng-pristine ng-valid ng-star-inserted" autocomplete="on" id="9_array-0-dc_title_alternative" name="dc.title.alternative" placeholder="" spellcheck="true" tabindex="0" type="text">',
      '<input class="form-control ds-form-input-value ng-untouched ng-pristine ng-valid ng-star-inserted" autocomplete="on" id="15_array-0-dc_identifier_QUALDROP_VALUE" name="dc.identifier_QUALDROP_VALUE" placeholder="" spellcheck="false" tabindex="0" type="text">',
      '<input _ngcontent-dspace-angular-c4223387587="" class="form-control scrollable-dropdown-input" id="17_array-0-dc_type" name="dc.type" readonly="" type="text" aria-controls="combobox_17_array-0-dc_type_listbox" autocomplete="off">'
    ]
  }
]
    (Attempt 1 of 3) should create a new submission when using /submit path & pass accessibility

[github-actions]

Hi @FrancescoMolinaro,
Conflicts have been detected against the base branch.
Please resolve these conflicts as soon as you can. Thanks!

[FrancescoMolinaro]

Hi @tdonohue , sorry for the delay on this one, I have adapted the code to handle also the native components from the form library, the PR should be ready now.

[github-actions]

Hi @FrancescoMolinaro,
Conflicts have been detected against the base branch.
Please resolve these conflicts as soon as you can. Thanks!

[tdonohue]

@FrancescoMolinaro : I'm looking at this after having reviewed #4777 from @AndreaBarbasso , and I feel this two PRs have slight conflicts.

In #4777, we have added labels to fields (like dates) which used the placeholder as a "label". This removes the usefulness of the placeholders on date fields.

So, arguably once those fields have labels, we could just remove their placeholders(which is what is recommended in https://www.deque.com/blog/accessible-forms-the-problem-with-placeholders/). That'd simplify things as we'd no longer need the configuration setting that you are adding in this PR.

If there are some fields where the placeholders are still necessary, then we could look at ways to remove those placeholders or fix the color contrast (if possible). So, I'd rather not introduce this new omitSimpleFieldPlaceholders configuration, because we should discourage people from using placeholders in general.