Metadata edit patch error fix

[Atmire-Kristof]

References

This PR closes #821

Description

This PR refactors the ItemMetadataComponent and ObjectUpdatesService to create a patch from the updates in the store and pass it on to the data-service's patch method instead of update. This allows us to create a better, more specific patch instead of comparing the old and new objects.

Instructions for Reviewers

Changes made:

• Created a MetadataPatchOperationService (implementing new interface PatchOperationService), which is able to transform a FieldUpdates object from the store into an array of fast-json-patch operations. This happens in two major steps:
  -- All updates are transformed into a MetadataPatchOperation. Each operation (add, remove and replace) has its own implementation of this wrapper object, each defining their own way to transform the information into an Operation.
  -- These operations are iterated over and modified depending on previous operations and finally added to the patch to return. (for example, when two values of the same field are removed, the second remove operation should take the first into account, because it might alter its position)
• This service can be injected using its token: METADATA_PATCH_OPERATION_SERVICE_TOKEN
• When an object-updates-entry is initialised, you can now optionally pass an injection token with it. This way, we can store the service it should use for creating patches into the object-updates store. This is exactly what we'll be doing for our ItemMetadataComponent.
• Added a method createPatch() to the ObjectUpdatesService, which injects our new service using the token we stored and calls the fieldUpdatesToPatchOperations() method to create and return a patch
• Modified ItemMetadataComponent to use this new createPatch() method and pass the created patch on to the data-service's patch method. It now also displays error notifications if the patch fails.

How to test:
Visit the edit-metadata page for any item and perform a bunch of operations on its metadata like adding, removing and editing values, as well as combining multiple operations at once.
Also try to reproduce the issue from #821, which should now be fixed.

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[tdonohue]

@Atmire-Kristof : just a quick FYI...this PR now has a minor code conflict

[tdonohue]

👍 Code looks good. I've tested it and verified that #821 is fixed. I also tried some complex patches, updated, adding and removing fields all in one request....and I ran into no problems. So, I'm satisfied that this is a major improvement over current behaviors (on main). If we notice minor issues later, we can resolve them in a follow-up PR. Thanks @Atmire-Kristof !

[LucaGiamminonni]

The code looks good. I have verified that #821 is fixed and I also tried other patches without encountering problems 👍