Avoid NPE at boot if a MetricsFactoryConsumerBuildItem contains null

[jmartisk]

Fixes #11736

[jaikiran]

Unrelated failure. It looks like we need to even @Disabled NativeMongodbPanacheResourceIT. I would have thought, extending a @Disabled ReactiveMongodbPanacheResourceTest would have prevented this one from being run. Apparently not.

2020-08-31T11:03:41.0574873Z 2020-08-31 11:03:41,029 INFO  [org.mon.dri.connection] (Thread-14) Opened connection [connectionId{localValue:13, serverValue:13}] to localhost:27018
2020-08-31T11:03:41.1270073Z [ERROR] Tests run: 6, Failures: 0, Errors: 2, Skipped: 0, Time elapsed: 27.365 s <<< FAILURE! - in io.quarkus.it.mongodb.panache.reactive.NativeMongodbPanacheResourceIT
2020-08-31T11:03:41.1278278Z [ERROR] io.quarkus.it.mongodb.panache.reactive.NativeMongodbPanacheResourceIT.testReactiveBookEntity  Time elapsed: 14.181 s  <<< ERROR!
2020-08-31T11:03:41.1283511Z org.awaitility.core.ConditionTimeoutException: Condition with lambda expression in io.quarkus.it.mongodb.panache.reactive.ReactiveMongodbPanacheResourceTest that uses io.quarkus.it.mongodb.panache.reactive.ReactiveMongodbPanacheResourceTest$IntegerAdder was not fulfilled within 10 seconds.
2020-08-31T11:03:41.1283910Z 
2020-08-31T11:03:41.1286135Z [ERROR] io.quarkus.it.mongodb.panache.reactive.NativeMongodbPanacheResourceIT.testReactiveBookRepository  Time elapsed: 10.386 s  <<< ERROR!

[gsmet]

@jaikiran @geoand has created a PR for it.

[geoand]

#11751