Upgrade ng-dynamic-forms to v15 and RxJs to v7

[ybnd]

References

• Fixes Update to ng-dynamic-forms v15 and rxjs v7 #1590
• Continuation of Upgrade to Angular 13 #1567

Description

Upgrade ng-dynamic-forms and rxjs, as well as a few others to fix the peer dependency mismatches that arose.

• isNumeric was deprecated as of RxJs 7.x; lifted it from 6.x into src/shared/numeric.util.ts

• Fixed a number of tests that broke, things to keep in mind for future tests:

  • debounceTime no longer works with fakeAsync/tick (open issue)

    I've added a temporary workaround based on this comment; it should work in the same way as the built-in operator but doesn't cause the same issue.

    We only need to use this workaround in cases where we're actually waiting for debounce in tests.

  • Subject objects now have a new currentObservers property which may be either null or [] when there are no observers. This makes it less reliable to compare BehaviorSubject objects directly.

    We had one case of this in vocabulary-treeview.service.spec.ts.

    This suite also contains a few other tests comparing BehaviorSubjects that don't fail. It would be good to refactor those tests to compare by emitted values instead, but that's a bit tricky since TreeviewNode contains nested BehaviorSubjects.

    Addressing that would take this PR beyond the estimated 8 hours (and seems out of scope).

Instructions for Reviewers

Run this PR locally and compare functionality & forms to https://demo7.dspace.org

Checklist

This checklist provides a reminder of what we are going to look for when reviewing your PR. You need not complete this checklist prior to creating your PR (draft PRs are always welcome). If you are unsure about an item in the checklist, don't hesitate to ask. We're here to help!

• My PR is small in size (e.g. less than 1,000 lines of code, not including comments & specs/tests), or I have provided reasons as to why that's not possible.
• My PR passes TSLint validation using yarn run lint
• My PR doesn't introduce circular dependencies
• My PR includes TypeDoc comments for all new (or modified) public methods and classes. It also includes TypeDoc for large or complex private methods.
• My PR passes all specs/tests and includes new/updated specs or tests based on the Code Testing Guide.
• If my PR includes new, third-party dependencies (in package.json), I've made sure their licenses align with the DSpace BSD License based on the Licensing of Contributions documentation.

[tdonohue]

👍 Thanks @ybnd ! Gave this a review and test today. Code all looks reasonable & has good comments (thanks!). Tested areas of the UI which appear to have been modified & some areas where forms are used (e.g. submission), and I'm not noticing any differences in behavior. So, this all looks good to me.

[atarix83]

thanks @ybnd for this PR

I've tested the application with focus on the submission form and all seems to work fine.

[tdonohue]

Thanks @ybnd ! Merging with +2