[Graph] Switch to SavedObjectClient.resolve

[timroes]

We need to switch over to SavedObjectClient.resolve instead of .get in the 8.0 release. This issue tracks work for the graph-workspace saved object loading.
This issue will also track progress for making Graph Saved Object share-capable. It has currently nameSpaceType: single. It should be updated to multiple_isolated.
For more details see #100489

[elasticmachine]

Pinging @elastic/kibana-app (Team:KibanaApp)

[jportner]

In case anyone is following this issue but not the linked meta-issue (#100489):

I published the Sharing Saved Objects developer guide, please take a look before proceeding with the implementation. And of course, please reach out if you run into any problems!

Note that there are a few more steps than just switching to use resolve(), there are some server side changes too, see the dev guide for more details. I think you only need to be concerned about Steps 2-4 but it would be good for someone on your team to verify 👍

[mbondyra]

I started working on this one, but let's wait till graph is deangularized before continuing. I will pick up the next one.

[elasticmachine]

Pinging @elastic/kibana-data-discovery (Team:DataDiscovery)