When impersonating an eperson, submissions cannot be start by uploading a file.

[pilasou]

Describe the bug

As administrator, it is possible to impersonate a specific user. When doing so, if the administrator try to submit a new item by first draging and droping a file in the designated area:

After selecting the collection, he/she ends up with a page that is uploading forever:

This does not occur if the user start the submission by selecting a collection.

To Reproduce

Can be reproduce on DSpace Demo site: https://demo.dspace.org/

Steps to reproduce the behavior:

1. Connect as admin
2. In the admin menu on the left, select Access control and then People.
3. Clic on edit button next to a user with submitter rights (i.e on demo site Submiter Demo)
4. On the edit user page, clic on Impersonate user button.
5. Go to MyDspace page
6. Drag and drop to start a submission
7. Select a collection
8. The infinite journey begins :)

Expected behavior

The submission page of the collection should be displayed.

[MMilosz]

Reproduced in sandbox.dspace.org. It looks like the /mydspace drag-and-drop never sets impersonatingID

(this is fine)

dspace-angular/src/app/submission/form/submission-form.component.ts

Lines 231 to 238 in 2f1bf85

	this.subs.push(
	this.halService.getEndpoint(this.submissionService.getSubmissionObjectLinkName()).pipe(
	filter((href: string) => isNotEmpty(href)),
	distinctUntilChanged())
	.subscribe((endpointURL) => {
	this.uploadFilesOptions.authToken = this.authService.buildAuthHeader();
	this.uploadFilesOptions.impersonatingID = this.authService.getImpersonateID();
	this.uploadFilesOptions.url = endpointURL.concat(`/${this.submissionId}`);

(this is not - notice missing impersonatingID)

dspace-angular/src/app/my-dspace-page/my-dspace-new-submission/my-dspace-new-submission.component.ts

Lines 89 to 93 in 2f1bf85

	this.sub = this.halService.getEndpoint('workspaceitems').pipe(first()).subscribe((url) => {
	this.uploadFilesOptions.url = url;
	this.uploadFilesOptions.authToken = this.authService.buildAuthHeader();
	this.changeDetectorRef.detectChanges();
	},

I'll push a PR in a moment. I need to check where else it's not set