NIFI-6949: When a Controller Service is removed, ensure that any othe…

[markap14]

…r service that it references is obtained via the ControllerServiceProvider to ensure that it is obtain to obtain and remove the reference, even if the service is in a higher-level Process Group

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Enables X functionality; fixes bug NIFI-YYYY.

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[MuazmaZ]

Looks straight forward

[pvillard31]

Went through the steps described in the JIRA to replicate the issue before/after the fix. Confirmed it fixes the issue. Merging to master.