Fixed Factory services not within the ServiceReferenceGraph.
bug #11639 [DependencyInjection] Fixed factory service not within the ServiceReferenceGraph. (boekkooi)

This PR was submitted for the master branch but it was merged into the 2.3 branch instead (closes #11639).

Discussion
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[DependencyInjection] Fixed factory service not within the ServiceReferenceGraph.

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets |
| License       | MIT
| Doc PR        |

Fixed a problem where Factory services are not added to the ServiceReferenceGraph.

Commits
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e992f8e Fixed Factory services not within the ServiceReferenceGraph.