Add FunctionalInterface To X509PrincipalExtractor #8175

Job	Run time
Check Samples	7m 7s
Build (ubuntu-latest, 17) / Build	11m 22s
Build (windows-latest, 17) / Build	18m 45s
Test Against Snapshots (17, 17) / Test	8m 31s
Test Against Snapshots (21-ea, 21) / Test	8m 43s
Deploy Artifacts / Deploy Artifacts	1m 27s
Deploy Schema / Deploy Schema	49s
Deploy Docs / Deploy Docs	1m 14s
Perform Release / Perform Release	0s
Send Notification	5s
	58m 3s

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