[7.x] [Graph] Fix graph saved object references (#85295)

[flash1293]

Backports the following commits to 7.x:

• [Graph] Fix graph saved object references ([Graph] Fix graph saved object references #85295)

[kibanamachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request
• Commit: 677e798

Metrics [docs]

Async chunks

Total size of all lazy-loaded chunks that will be downloaded as the user navigates the app

id	before	after	diff
graph	1.3MB	1.3MB	+856.0B

Distributable file count

id	before	after	diff
default	47320	48080	+760

Saved Objects .kibana field count

Every field in each saved object type adds overhead to Elasticsearch. Kibana needs to keep the total field count below Elasticsearch's default limit of 1000 fields. Only specify field mappings for the fields you wish to search on or query. See https://www.elastic.co/guide/en/kibana/master/development-plugin-saved-objects.html#_mappings

id	before	after	diff
graph-workspace	9	10	+1

To update your PR or re-run it, just comment with:
@elasticmachine merge upstream