[Image Embeddable] Use client-side authc.getCurrentUser from core.security

[tsullivan]

Part of #186574

Background: This PR serves as an example of a plugin migrating away from depending on the Security plugin, which is a high priority effort for the last release before 9.0. The Image Embeddable plugin uses the authc.getCurrentUser method as a means to allow the user to delete image files that are attributed to them.

Checklist

Delete any items that are not applicable to this PR.

• Unit or functional tests were updated or added to match the most common scenarios

[elasticmachine]

Pinging @elastic/appex-sharedux (Team:SharedUX)

[kibana-ci]

💚 Build Succeeded

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• Commit: b979229

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
imageEmbeddable	66.9KB	66.9KB	-4.0B

Page load bundle

Size of the bundles that are downloaded on every page load. Target size is below 100kb

id	before	after	diff
imageEmbeddable	5.7KB	5.7KB	-49.0B

Unknown metric groups

References to deprecated APIs

id	before	after	diff
imageEmbeddable	2	1	-1

History

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