Delete pending json patch operations

[alemarte]

References

• Fixes Pending json patch operations should be canceled when leaving the submission page #1217

Description

When the user leaves the submission page the state related to the aborted submission must be totally erased.

Instructions for Reviewers

To achieve the goal a new NgRx Action has been added (DELETE_PENDING_JSON_PATCH_OPERATIONS). This action is dispatched on the OnDestroy hook of the SubmissionEditComponent. The reducer destroy every data related to the aborted submission.

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[tdonohue]

👍 Thanks @alemarte ! I've tested this today... I was able to verify the bug from the ticket using the demo site, and verify also that this PR fixes that issue. The code looks good and it comes with tests to prove it's working as expected. Thanks!